I would say upgrade it because the value of having apps on the phone outweighs the slight lag, instability, and other issues with 2.0.1. Hopefully the next version will further fix these issues so there will be little incentive to not upgrade.
Thats good, thanks for the info. I was just wondering because everyone talks about it on the 3g, and not the 1st gen, and that made me wonder a bit since 2.0 was supposedly bad on the 1st gen.