I don't know how they could put a quad-core processor in a phone and keep it cool. These current smart phones (single core) are bad enough, peaking at almost 120 degrees, sometimes more if your phone is seriously overworked. We haven't really even seen how a dual-core behaves long term. I just think about my PC and the huge heat-sync I just put on my new processor, and then I look at the size of these phones and wonder...how can this be realistic in practice? There is always a trade-off when you jump ahead with one technology and the rest hasn't caught up....Look at 4G on the Thunderbolt, it's super fast, and the battery sucks. First things first we need some advances in battery technology, because processors eat up battery life, too. With that said, to every rumor there is some truth, but this could still be aways away, or there could be serious drawbacks.
Another thing you have to consider is the fact that Android is not optimized for Dual-core, and this means that on Froyo a single-core is better. My understanding is that not even 2.3/Gingerbread is going to be fully optimized for dual-core, and we might have to wait for 2.4 to see full Dual-core support. What on earth are we going to do with a quad when they haven't even caught up with a dual?! Additionaly, the best processor chip varies depending on what you are doing. Furthermore, you can't overlook software, which can make up for less-than-dazzling hardware.
I'm starting to ramble and digress. Anywho, that's my 2 cents.
P.S. Don't wait for the next best thing, or you'll always be waiting. Sign a 1-yr contract...it's usally around 70-80 more and you can upgrade as soon as 10 months in (depending on carrier). The Bionic is RIGHT around the corner
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-Sources: I work in the wireless industry for the Best carrier
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