It is most likely that Opera 9 will see the daylight next year, not just previews or betas, but also a final release. For most people Opera 8.5 wasn't much of a change compared with 8.0, due to the nature of the release, which was being without ads. Opera 9 will continue to be without ads, but will offer significant changes, to summarize all the changes seen in Opera 9 Preview 1 and features exposed via several blogs and forum posts.

Web standards support
Back in the pre-Opera 7 days, other browsers has better or more recent standards support, but all of that changed and Opera currently has good web standards support and tries to add new ones while they are being created.

• Atom 1.0
  A new syndicate format, which has some strong points compared with RSS 1.0/2.0.
• XSLT 1.0
  XML Transformations, an XML based stylesheet language, compared with CSS which has its own definition of defining layout.
• XPath 1.0
  XML Path Language, to search and navigate through elements and attributes in an XML document.
• Web Forms 2.0
  This proposal provides new key elements to improve the very basic HTML4 forms. Besides this it tries to standardize and document the interaction of forms with other standards like CSS and HTML forms.
• Web Apps 1.0 Canvas element
  A proposal specification, just like Web Forms 2.0, which extends HTML and DOM to make it more suitable for application development. Currently Opera 9 only implements the canvas element, which allows dynamic graphics, such as simple searchlights, reflections or even simple 3D first person shooter games.
• Some CSS3
  The most requested CSS3 property, opacity, for transparency support might be coming to Opera 9. I would also like to see curved corners, which are being used more often these days. Both effects can be (partially) simulated with transparent PNGs though.
• Partial SVG Basic 1.1
  Opera already supports SVG Tiny (SVGT), a subset allowing SVG elements for mobile phones. SVG Basic (SVGB) is in the works and adds more features. Still SVGB is a subset of SVG, while SVGT is a subset of SVGB.
• TLS 1.1 and TLS Extensions
  Newest standards for secure transmission and datatransfer.

End user standards support
Web standards support is great, but what does this mean for the developer and end user? Also, sometimes non-standard features exist, like styled scrollbars or the devilish blink tag.

• The Acid2 browser test
  Opera 9 strives to be fully compliant with the Acid2 browser test designed by the Web Standards Project (WaSP), to show off the implementation of several W3C standards.
• Rich Text Editing
  An often requested feature to allow rich text editing (to give text several ways of formatting) in web forms. GMail is a good example of showing the RTE support at work, while compasing a mail message.
• OPML (Thanks Kildor!)
  Outline Processor Markup Language support is being added and demonstrated to work with Opera Mail's RSS feeds. This XML specification allows exchange of outline-structured information. In this case it would make it possible to import and export RSS feeds between Opera and other OPML supporting aggregators.

Plug-in support
Still problematic, and not as smooth as Firefox, Opera uses Netscape plug-ins as well, but has no automatic installer to assist the user. Although strifing to a unified plug-in API will greatly help make plug-ins work on any browser, a graphical meaning of assisting the user has not presented itself in 9.

• Netscape plug-in API Extensions
  As previously issued by Opera Software and the Mozilla Foundation, several browser vendors are working together to modernize and unify the Netscape plug-in API.
• Macromedia Flash 7, 8 or?
  Currently Opera 8.51 ships with the latest version of Flash 7, while 8 was already released before that. Why? Because Flash 8 introduces a lot of features but has increased substantially in size to 1.25 MB. Considering Opera normally is less than 4 MB, this greatly affects the overal download size. Perhaps Opera Software should remove Flash from the default setup, and offer it as an optional (dialog triggered) download, just like Voice and Java support?

Opera Mail (M2)
Currently Opera Mail seems to be just the same as always. Ok, back-end work is great for stability and standards support, but real mail functionality has yet to represent itself in 9, if at all, as 8 didn't feature anything special either.

• Improved IMAP back-end
  Opera already supports the IMAP mail protocol for receiving and sending, but in Opera 9 this will be greatly improved to better support this standard.
• New mail storage system
  Opera 9 will change the mail storage system once more. This time the triggering effect of this are anti-virus programs. If an anti-virus program detects and deletes an infected mail, it could very well whipe out your entire mailbox file, losing a month of mail. By changing the way how Opera Mail stores mail, these kind of serious incidents can be reduced with lesser damage.

New features
All the above is great, but how does an Opera user "feel" that it's a next-gen browser release? What makes Opera 9 so different from 8 from a user's perception? Although the changes may seem little, please note that a lot is still unknown and it's still early in Opera 9's development. Of course Opera 9 already has a rich feature set inherited from previous versions, surpassing Firefox 1.5 as it is.

• opera:config
  The simplification of the Preferences window in Opera 8 will continue in Opera 9. No, don't go boo and aah right away. This is purely done on the road to simplifying the Opera experience for a wider range of people. But to addresse the concerns of the more advanced power users, Opera Software has designed the opera:config window, which not only lists all the advanced settings, but also nicely groups them, so it can easily be managed.
• Site specific preferences
  Currently Opera 9 supports site specific preferences through the ini file. However, it can be anticipated that some sort of graphical user interface will be build around it. Site specific preferences allows the user to specify specific settings for webpages, eg. setting a browser identification, or disable plug-ins.
• Editable search engines
  A next preview of Opera 9 will allow the user to add and configure the search engines. Previously this work was done through editing search.ini, but this will be made much easier with a graphical user interface.
• Lockable tabs (Thanks olli!)
  This new little nifty feature allows the user to lock a tab, meaning it cannot be closed. This is especially handy if you have certain news sites, mail or chat tabs open of which you want to prevent them from closing while you do other (tabbed) tasks in the same Opera window.
• BitTorrent support?
  It drew a lot of attention when it was tested in some 8.10 Preview long ago, and still a lot of people ask for it. Opera Software should work on finalizing support for BitTorrents, and release the very first browser which natively can download these peer-to-peer network files.

Conclusion
All in all, Opera 9 seems to become an exciting release, and it no doubt will be. Unlike Firefox 2, Opera is adding not too many new features at the present time. Opera Software's approach is by improving the back-end, and adding several new key features they still can win new users over from other browsers. To ease the transition Opera heavily relies on its base set of rich thought out features and simplifies the graphical user interface, while trying to maintain flexibility for the advanced power user. If these additions will get more Firefox users over? Probably not, as some will be available by default or through extensions. However IE users and Opera users will be very happy with it.