Alien Swarm

Similar to how I got Portal, Alien Swarm is free today on Steam (The SDK and dedicated server are also free!).  Get it while you can.

I'd heard about this a few days ago, and wondering what exactly it was, I read an article, found that it was originally a UT2k4 mod, so I downloaded and installed that to see what it was like.  After having gotten the Steam version, I can say this: the two are vastly different control-wise.  Specifically, the Steam version is a couple metric megafucktons better.  You don't have to switch marines for every little menial task anymore.  There isn't any stupid right click menu anymore.  You can order your tech guy to seal or unseal a door without changing marines.  More complex things (that the specific marine has to do, like hacking panels or healing) still require switching, but that's excusable.

The AI is a lot better too.  In the UT2k4 mod, the AI marines liked nothing better than just standing about half a screen away from you not doing anything while you were busy trying to kill things.  Now they actually fire at things.  They also run into a nearby heal beacon if they need healing, which is nice.

The Steam version has a much greater emphasis on multiplayer, to the extent that the single player is only a practice mode.  To contrast, there were single player campaigns in the UT2k4 mod.

My main issue with the game is that changing weapons with the scroll wheel is WAY TOO SENSITIVE.  Most of the time, I end up re-selecting what I originally had selected.  Which is a huge problem when I'm controlling the healer and trying to drop a heal beacon and then go back to shooting things.  I ended up wasting two beacons.  It was this way in the UT2k4 mod as well, which is strange given that I have no problems switching weapons in regular UT2k4 gameplay with the scroll wheel.

Also, for one reason or another (I believe I had issued a follow order at the time...) I lost a marine (only one) in the practice level because he didn't fucking follow the rest of the group.  I was trying to get him to weld a door shut (with Faith selected, using Shift+4), but the door kept opening instead.  I decided to just run, since this was right at the end of the practice mission, and he didn't follow and died.

One thing I can say: don't overlook flares.  Their purpose, despite their name and obvious visual effect, is to give your weapons autoaim.  If you're getting rushed, toss a flare into the enemies and fire away.

Overall, Alien Swarm looks like it'll be a really fun co-operative multiplayer experience.