Someone advised that the E50's will be out in August. Try before you buy.
I can understand KeybG frustration in waiting for Yamaha. I'm tempted to buy the PSR1500 NOW. Waiting till next year is a bummer, but time is on our side. (time is on my side, yes it is(Stones) ) The longer you wait the better the board, and at a similiar price. I haven't heard the E50, but the PSR1600 will blow the socks off it, IMO, without hearing either. It will probably have some megavoices, maybe even a few SA voices.
I suspect that Roland's messed up marketing will price the E50 close to the PSR31000 not PSR1600, which will make the PSR1600 a super value.
Starkeeper