Hmm don't have those problems with mine yet and the computer is 3 years old. I am a little concerned about the potential for the 8600M GT problem that might arise with this computer, but as I understand it, it will be covered by apple care. Other than that, this computer is great to use for being just $350.
Mine's almost 5 years old now, and I've had all of those problems, just not to a severe degree. Temps are starting to get a bit out of hand-- running at 79 right now even with a notebook cooler-- but it's HOT in this apartment (temporary living arrangement) so I won't complain. I plan to keep this notebook for another 3-4 years, if it lasts.
I would love the 17"! I have always wanted a 17 and even got a Santa Rosa one for a bit, but sold it for a cool $700. Someone wanted it even more .
My biggest regret has been not going for the 17". Two of my friends have them and they're amazing machines. But one of those friends is moving to a 12" Tablet PC (partially for school, partially because of the size/weight) so I guess it gets old after awhile