Since the Christmas release of a pre-alpha build of Opera 10.50, our developers have been working hard to get the Windows version in beta shape: check out the Opera 10.50 beta page for all the latest features and enhancements. Personally, I really dig the Aero Peek thumbnail previews that pop up when you hover over the Opera icon in the taskbar. And oh, Opera Unite has landed in the 10.50 branch as well :-)

Note that Opera 10.50 for Mac OS X and Linux haven't reached beta stage yet, but you can get alpha versions for these platforms from the Desktop Team blog.

Next up: standards support. If you haven't done so yet, have a look at Shwetank's blog post for the pre-alpha, all of which is still valid: super-fast JavaScript with Carakan, advanced graphics with Vega, and support for CSS3 Backgrounds and Borders, Transitions and 2D Transforms, Offline Storage and more.

This beta adds support for HTML5 <video> , and Patrick and Bruce have prepared a Dev.Opera article on this for your enjoyment: Introduction to HTML5 video — be sure to not miss out on the fine examples included throughout the article!

Another major feature in this beta is our new Opera Widgets implementation: widgets can now be run independently of the browser instance, and integrate nicely with the platform they're running on, effectively allowing developers to create standalone desktop applications with Web standards. Debugging can be done while the application is running, through Opera Dragonfly's remote debugging feature. Get started and build your own apps with our updated Widgets SDK documentation.

One caveat: I recently blogged about improved Web Fonts support in our pre-beta snapshots, but for the beta release, this has unfortunately regressed again. Web Fonts work under certain circumstances, but break in others. Don't let this spoil the fun though — our devs are working on a fix.

It's also worth mentioning that we've thoroughly reorganized the menus: if you open the Opera menu, choose Page Tools > Developer for options such as View Source, Validate, and Developer Tools. Speaking of which — Opera Dragonfly is now using a new version of the Scope API, which results in better performance and a couple of other enhancements, such as a handy pixel magnifier and color picker. Head over to the Opera Dragonfly blog for more details, and the announcement that Opera Dragonfly is now an Open Source project hosted on BitBucket.

That's all for now — let us know what you think!