what determines the depth of 3d is it the tv or the content shown because the companies have only really just started selling them and they have so many different series and models avaliable its confusing also what in detail should you look out for in terms of specs etc when buying a 3dtv just because theres many brands and series

Content determines the depth of what you see. All 3D TVs will all show pretty much equal depth if they are told to do so by the 3D movie or game... So you shouldn't be buying one based on howmuch depth you see. Issues like ghosting, refresh rates and compatibility is what you should look out for.

I suggest to go through this thread for a lot of discussion about 3D TVs recently -

http://gamrconnect.vgchartz.com/thread.php?id=113443&page=1&str=1038272088#

cool so there pretty much all the same just with very small unoticeable differences like back lit and egde lit led or plasma which is better