Well you'll just have to wait for all the devices to launch before making a final decision. I would imagine that Samsung has been able to correct many of the issues they had with the Galaxy S, and as long as they could figure any LTE issues out, the Charge may yet be a very good device. It has the best screen you could ask for, though the design, esp. physical buttons is not that appealing. MicroSD's are relatively cheap now though, so I don't see that being an issue. Pretty much my only issues with it at this point are the physical buttons, and that its not a GS2. We haven't heard much on the Revo yet, but it isn't likely to be much different than the T-Bolt. LG is known for making very good phones, but the specs are of course lacking and will seem even more dated by the time this phone actually launches. And reports at this time point to it having all the Bing garbage on there, meaning a root is almost mandatory for many people (like me).
Remember also that we still don't know yet whether the Bionic-Etna is actually cancelled or not, it may yet head to market soon. And the T-Bolt's Gingerbread update in June may very well correct its battery and network issues, making it a much more compelling device, even if the hardware is a bit lacking. What I'm doing is waiting until they warn us of the specific date that unlimited ends, and I'll go down a few days before the deadline and pick out the best LTE device they have out by then, whatever it may be. Who knows, we could have the Targa and/or the GS2 LTE by then, or we may just barely have the Charge out. Wait and see.