they didn't release caspian border for the consoles because DICE wanted to stress test the servers for 64 players, and considering the consoles have 32-player max, it wouldn't have made any sense. that and the fact that the beta build that is currently available is over a month old and hurriedly put together because microsoft and sony wanted something out there before the game's release, so they decided on a smaller-sized map like Metro to limit the download size for consoles.
edit: also, for the people crying about the graphics on the consoles, there will be an optional high-res texture install for the 360
http://bf3blog.com/2011/10/battlefie...-res-textures/