Intel released some new drivers for their integrated video chipsets earlier this month and the improvements are MASSIVE!
Some improvements I have noticed:
Increased stability, especially in Vista (less BSODs, less "driver has stopped but recovered" messages, etc)
Increased frame rate in games
Games no longer go black for brief moments.
GMA 3xxx users FINALLY get HARDWARE vertex shader support enabled!
This allows games that wouldn't play due to a lack of vertex shader support to finally be able to be played.
Stuff now WORKS on the 965G and G33! The framerates are just barely playable but it will be fine for the occasional gamer. (I do suggest a REAL card though, low 20s-low 30s FPS is not what I call good performance)
Now I don't personally use the Intel GMA chipset (I have a REAL video card!), but ALL my roommates do. Their PCs run better, stay running longer between reboots and they can actually fire up some of the older games and PLAY them.