I have a 2010 mbp 15" with the intel igp and the nvidia. I used to run on intel exclusively to save battery time (intel only lasts over an hour longer). However lion doesn't even run smoothly on the nvidia let alone the igp. Full screen safari is a joke on the intel, stuttering all over the place. It made me have to switch to nvidia only, draining the battery. Sigh.
I can imagine your frustration.
Sometimes I think Apple is doing this on purpose so every needs to upgrade the hardware. But seeing the latest MBPs have bad graphical performance I have to reconsider this.