When I first started thinking about it and studying it, I found it downright exciting. So much potential. But as with most thing the devil is in the details. And we just don't have enough details yet. So much could change between now and when it actually gets implemented that it may turn out to be a big disappointment.
I think there is a little confusion here. CDMA is a technology, GSM is a standard. So its not comparing apples to apples. The right comparison is between TDMA and CDMA or between GSM and CDMA 2000. From a technology viewpoint, most people would agree that CDMA has clear advantages, which is why GSM's 3G variant is based on CDMA. From a standard's point of view, GSM wins because it has things like SIM cards and widespread availability leading to economies of scale. When it comes down tp picking a particular operator and price plan, that has more to do with local regulation and carrier marketing than the technology or the standard. Near me Verizon has the best network because they put up the most base stations. T-Mobile is the cheapest because they have to compete with the others harder as they are the smallest.
I live in San Francisco ("the City"), and I'm a huge fan of the place. And the previous posts are right about there be more social life, by far, in SF. But given your situation, I would think carefully about Mountain View. There's so much talent down in the valley. The city tends to be younger and more design-centric. And Mountain View or one of the towns near it is certainly far cheaper.
Also, it depends a lot on you what your start up ideas involve. I would look at the Peninsula like an OSI 7-layer stack. San Jose and the South Bay are the lower layers, and then as you move north, you work your way into the higher layers. There is a definite clustering of expertise anchored by a a few big companies in each area. Core networking and silicon bending are done in San Jose by Intel, AMAT, Nat Semi., Layer 2-3 are down close by with Cisco. Mtn. View, Palo Alto, and San have some great middleware and web software - Google, Yahoo, Oracle. Then SF is a lot of UI and Application layer work. To be fair, the city is attracting a whole new wave of start-ups. And my OSI model has all kinds of glitches (like Apple being so far south). but I still think its a good guide line. If you're doing something similar to what Google does, it might make sense to be physically close to them.
And I'll say it again, the South Bay is much cheaper.
Looks like RIM has begun accepting applications to their store. Has anyone gone through the application process yet? I'm glad they got it out, and its not the much past their original December launch date.