When it comes to Need for Speed, I've known that franchise since the freaking 3DO, and I've enjoyed a few of those games quite a bit. I think the very best Need For Speed, at least for me, was the very first Need for Speed Underground on Xbox 1. However, Underground 2, came out the next year, and personally, I thought it was crap. Then we got Most Wanted on the 360, and I actually thought that was a pretty good launch game, and somewhat underapreciated. Then Carbon last year. I tried the demo on Xbox Live and even rented the 360 version, but I have to say that Carbon just didn't do it for me at all. The Graphics were barely above Xbox 1 standards, and the whole idea of having a crew that you raced with, didn't appeal to me.
As for sequals in general, I just don't think the "We might as well release a new one every November" theory works in the long run. You end up Tomb Raidering your franchise, and then you have to hope that somebody comes along and resurrects your franchise from the ashes. Of course, as long as the sheep continue to hand over their cash for these yearly updates, the EA Canada's of the world will keep churning them out. It's kinda depressing, but hell, just look at the summer movies we got. Spiderman 3, Shrek 3, Pirates 3, ad naseum.
I think we should definitely give some love to the new IP coming out this year:
BioShock
Mass Effect
Uncharted: Drake's Fortune
Heavenly Sword
Lair
Blacksite: Area 51
just to name a few.