Whenever I turn on anti aliasing through the game's options numerous parts of the screen become covered in strange squares. It happens whether its 2x, 4x, or 8x anti aliasing or if its on msaa, adaptive msaa or ssaa. Strangely if I force anti aliasing through the catalyst control center it doesn't work in game, but the selecting the mode of anti aliasing does work. Is there any workarounds for this? Im using the 12.3 drivers and the Skyrim 1.5 patch.

It's a problem with the 12.2/12.3 drivers for AMD cards. For now the only solution is to turn off AA, or go back to the 12.1 drivers. Hopefully AMD will fix it soon.

Is there any reason why forcing AA through the driver isn't functional in skyrim? It seems to work for me when I turn it on in other games. It also makes me wonder if anisotrophic filtering forced through the driver is working.

ATi Radeon are still getting their drivers together, bro...
I mean it has only been five months or so. Cut them some slack!
(Meanwhile, I'm really enjoying nVidia's new Adaptive VSync - it's miraculous.)
But don't give up hope.
Patience is required (and antialiasing is really not).

They have fixed it. OP needs to uninstall his current drivers and reinstall with the real 12.3s.

@ the OP - what's the install date on your 12.3s? 12.2, which is the problem driver, incorrectly reports as 12.3 in the CCC. However, it will have an install date of prior to March 28th, which is when the real, unborked 12.3s came out.

In order to get the problem to go away, you need to completely uninstall your current drivers and install the correct 12.3 set. If you don't know how to do that, follow the instructions provided http://www.gamesas.com/topic/1368527-graphic-issue-pixelated-like-image/page__view__findpost__p__20665695.

Yes Tyraa that worked thanks a lot. Strangely it still says that last software update I had was from march 10th though.