Buy Nexus Now or wait for new (2012)Nexus

I have a problem, it's pretty simple. Just need suggestions.

I'm on Tmobile... it's LTE network will be launching next year (2013). I want to have a phone compatible with it's new network but I'm not too sure that this year's Nexus will launch with the radios. I know Sprint's Nexus device launched before it's LTE network but I'm not too sure tmobile will do the same.

Also I really want the Cortex A15 chips. I know that OMAP 5 is projected to release 'late 2012 to early 2013'. So I'm also not sure it will have an A15 chip yet.

So should I buy the Gnex now? Do you guys think it will suffice until the (2014) Nexus? Or should I say, do you think it will be supported throughout 2013....