I would like to play but I don't like the idea of decks only being good for so long. How long is the average time before the decks are cycled out?
T2 standard is always going to be the core set with the the latest expansion set. So in this case, we'd have in order of release:
Innistrad Expansion Block (Innistrad, Dark Ascension and Avacyn Restored)
Return to Ravnica Expansion Block (Return to Ravnica, Gatecrush, ???)
Basically it's always going to be the latest expansion set plus the latest core block. When M14 is released, you will phase out M13 and the Innistrad sets ...the only ones legal then will be M14 (when released) and the Return to Ravnica Expansion Sets.
Hopefully that kinda makes sense on rotation. Expansion will include back 2 core sets plus expansions, so off the top of my head, it prob is M12, M13, and all Sets From Scars of Mirridon on. Don't quote me on that but I believe that would be correct