Signing up for sourceforge was less of a hassle than most sites. Really, all the questions you have to answer fit on one screen and its just your name (lie), email, password, unclick the choice that sends you spam, then click the button to say you are 18 (lie if you have to). It will take you longer to read this post than to do all that.

Some statistics available on the page for the competitors in the category:
downloads in last 12 months
32,604 Crystal Space 3D SDK
152,676 Irrlicht Engine
231,828 FreeCol
482,832 OGRE (O-O Graphics Rendering Engine)
1,180,080 OpenKore
92,175 PCGen :: An RPG Character Generator
1,392,651 ScummVM
485,012 Tremulous
232,904 UFO:Alien Invasion
147,678 XBMC (Xbox Media Center)
One thing is that the openlierox downloads can be found on many other pages so we may be missing count of some. For example some people find it on a mac games website, a free games website, or some place like that. Another thing is that the openlierox downloads weren't even on the main lierox page for a while until somewhat recently, I forgot when but it used to just have the LieroX download then someone made a post saying to make it more friendly to newcomers and it got done.
The way some of these other projects pick up fans easily is they are based on older games that had commercial releases and the fans are still around. Liero has never had such exposure, despite being better than most commercial games. Maybe it could get more exposure if it was released as part of packages that new computers get, or if a version was made for xbox or wii that let four console players join the other online servers (this could be really popular, right now simpler more causal games are a growth market and if you talk to people who work in game marketing it is like one of the new marketing fad theories). Anyway show me a project based on a game that has never had a commercial release that has this amount of fan made levels/skins/mods or size of community. I think OLX deserves an honorable mention just for this, but in the least, we could aim at kicking "Crystal Space 3D SDK" out of no. 10 and getting some exposure through that.
A couple things in the new betas that seem to make the game much more easy to get into for disoriented noobs, is the part where on the weapon selection page it tells you your keys. So often before that it was a conversation to explain to noobs why they need to look at their keys before going online! One more thing that would help is having by default the "any key press starts chat" turned off, as that is the other major hurdle new players have once they learn their keys but find their keys mysteriously frozen in game not noticing the little chat that has started absorbing their keystrokes. Another great new feature is the limited time to choose weapons, though it would be better if people who didn't finish within that time had force random applied to them instead of being kicked. The last thing that would make the game more easy for noobs to get into, is instead of having the non obvious double clicking the red name to download a new level, have a "download new level" button. This last paragraph worth of comments probably I should put in the game development section but I just bring it up here because this thread is about increasing the exposure of the game, and increasing the ease for noobs to get started is a big part of that.
-nihil abyssyncyst