My Opinion
I'd have to go thunderbolt hands down.. I'm a full fledged phone junkie, and before I had Verizon, i switched phones every 2 months... Only the Droid could have kept me entertained for a full year... now that the year has been up for a couple months, I'm ready for something new
Besides that, from a techy's POV, although the Thunderbolt does not have dual core like the Bionic, there are some main cons against the Bionic in my opinion.
The HTC Thunderbolt, although it only has a single core Snapdragon, it is an updated, modern version of it, so it's not the same processor that's in the EVO. Also, the Thunderbolt has more RAM than the Bionic (although, as I understand, it is DDR instead of DDR2). All in all, I think the Thunderbolt, performance wise isn't that far off from the Bionic than a lot of people think.
Some people think that just because the Bionic is dual core thinks that it is the ALL-END-ALL, and that makes it the best phone ever. That's not the case at all. Dual core mainly has to do when you're multitasking with many apps running at the same time.
Also, for me, the fact that the Bionic has Blur is a major con to me. I've always loved the HTC Sense layout and all of the addons that come with it.
So besides the fact that one phone is dual core and the other isn't; one has more RAM; and one has a different variation of the OS on it, the only other thing that's different is the form factor.
IMHO, although dual cores in Mobile devices (smartphones, not tablets) is a huge deal. Quad Cores are going to be out this fall and these phones we are debating (in a senseful manner) about today are all going to be outdated in the technological world. That's the cycle of today's technologies, whether it's phones, or computers (my specialty

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