If you are even considering the Thunderbolt, I'm guessing it's because of money... and if that is the case, why buy any smartphone. Because there are so many newer smartphones, with better screens and much better hardware out there right now. HTC Rezound if you are looking for an HTC phone... Droid RAZR and this week the Droid RAZR MAXX from Motorola... LG Spectrum just came out with HD screen.... all dual core... and all will get ICS well before the Thunderbolt.
I bought my thunderbolt the week it came out, and have never had a regret. I dealt with the initial issues and glitches, knowing that issues were sure to be encountered with a brand new device. This has turned or to be a great device. I would recommend it.
I originally had a Droid X and it was a nice device but after updating to my Thunderbolt I haven't looked back. Both devices are nice but i prefer the TB and as for battery life the Droid X is better a little bit but after placing the Rezound or extended battery that puts Tb back on top.