MPlayer is one of the many available media playback systems for Linux and Unix-like operating systems and is particularly useful to many people thanks to its support of proprietary and non-standard video formats.
While the use of these formats will undoubtedly be controversial, the pragmatic Linux user will often still want to be able to enjoy media in these other formats, which makes MPlayer a good solution.
Inside your web browser, however, MPlayer's default plugin interface does not feel very integrated visually with the rest of the system.
Gecko-MediaPlayer is a custom browser plugin which uses MPlayer and its GNOME bindings to provide a better user interface for playing audio and video inside your browser. Any media playable by MPlayer that you come across online can be played back through the plugin, just like the mplayerplug-in package, but with a vastly improved user interface that feels integrated with the GNOME desktop.
Installing the Gecko-MediaPlayer plugin is generally as simple as installing the gecko-mediaplayer package. You may want to remove the mplayerplug-in package first if it is installed, to avoid conflicts between the two browser plugins.

Once you've installed and restarted your browser, any media that MPlayer can handle will show up in the new interface.

If you're a GNOME user that also chooses MPlayer as their media solution for the web, installing this package is a quick and easy way to improve your online viewing experience, through a better integrated UI.

Just a quick note to say that the second most popular web browser out there and one of the most used bits of open source on the desktop, Firefox has had version 3.0 go gold.
Unfortunately, at the time of writing Mozilla's servers are down following an attempt to win Firefox a Guinness World Record for being the software most downloaded in 24 hours. The sheer weight of traffic attempting to snag the new release and help achieve the record has brought pretty much every Mozilla site to its knees.
Still, when things do come back up, be sure to grab yourself Firefox 3.0, get your Firefox-using friends (on all platforms) to upgrade and of course help convince others to switch!
Once it's back up, you'll be able to get Firefox here.
UPDATE: I've now managed to get on the site, so the links might well work again. Or they might go back down... YMMV.

The first release candidate version of Firefox 3 is now available from Mozilla.
If you're already using the beta of Firefox 3, which many people on the latest Linux distros will, it is unlikely there will be that many functionality changes and new features in this RC release, but it is designed to bring greater stability and move closer towards the final release of Firefox 3.0.
Having said that, this new RC does have some new features that don't make an appearance in the most recent beta.
Cited are some new user interface improvements, which improve the consistency with Firefox on each platform it is available from. There are also some updates to the location bar, among many backend changes.
The RC1 release is available to download, see the announcement for download links and more information.