We get it, you're not about to give up ______ (fill in the blank with Chrome, Firefox, Safari, or IE), which other browser makers will have to pry from your cold, dead hands. But aren't you the least bit curious what the competition is up to?

Now is as good of a time as any to give the Opera browser a whirl. The second Release Candidate for Opera 11 is just a click away, following the release of the first RC that was posted just one day ago. This followup RC mainly addresses a handful of tab stacking issues, otherwise Opera Software promises "Opera 11.0 is mature enough to be prepared for a final release."

In addition to tab stacking, the major new feature in Opera 11 is the long overdue support for extensions. Other features included baked in visual mouse gestures, better performance, search predictions from Google, and enhanced HTML5, to name just a few.

You'll have to wait until next year before getting a chance to play with Firefox 4 in Release Candidate (RC) form. An updated release schedule shows the RC version being pushed back until early 2011.

"Development on Firefox 4 has not slowed down, and strong progress is being made daily. However, based on the delays in completing the 'feature complete' Beta 7 milestone against which our add-on developers and third-party software developers can develop, as well as considering the amount of work remaining to prepare Firefox 4 for final release, we have revised our beta and release candidate schedule," Mike Beltzner, VP of engineering for Firefox, wrote in an mailing list message earlier this week.

There have already been six beta version of Firefox 4 released in the wild, but after more than a month and a half of development, Firefox 4 beta 7 has yet to materialize. The problem, says ZDNet, has to do with issues integrating Firefox's older TraceMonkey engine, as well as trying to mesh the new JaegerMonkey engine.

Microsoft's Windows 7 Team sent out an email this morning reminding Windows 7 Release Candidate (RC) users that the free ride is almost over.

"While most people who tested Windows 7 have now moved to the final version, some are still running the Release Candidate. If you haven't moved yet, it's time to replace the RC," the Windows 7 Team wrote.

In case you're fuzzy on the dates, here are the ones to remember:

• March 1, 2010: PC's with Windows 7 RC installed will begin shutting down every two hours. Work will not be saved during these shutdowns
• June 1, 2010: Windows 7 RC fully expires

Once June 1 rolls around, you may continue to use the RC in two hour spurts, but you'll also have to tolerate a solid black background with a persistent message on the desktop, as well as periodic notifications alerting you that your copy is no longer genuine.

The good news (for some of you) is it's tax time, so if you're getting a big refund this year, you can add Windows 7 to the list of annual computer upgrades.

On October 29, which is now less than a week away, Linux users will have a new Ubuntu release to play with. But if you just can't wait that long, especially with all the hoopla surrounding the launch of Windows 7 making you jones for a new OS, consider downloading the Ubuntu 9.10 Release Candidate that was just made available.

"We consider this release candidate to be complete, stable, and suitable for testing by any user," the Ubuntu team wrote on its blog.

Several new features have been added to the open source OS since the release of Ubuntu 9.04. For example, 9.10 makes the transition to Upstart native jobs for faster boot times, Empathy has replaced Pidgin as the default messaging client, the latest release ships with Ubuntu One, a personal cloud computing app allowing you to backup, store, sync, and share data with other Ubuntu One users, Canonical claims the inclusion of new Intel video driver architecture solves "major performance problems," the new ext4 file system is now used by default, and a whole bunch more.

See the full list of changes (and known problems) here, and if you're itching to try out the RC, you can download your copy here.