X11 is still GPU viable (DASH) - for now - if you have an efficient rig (NVidea and AMD both do well on X11 mining, NVidia wins for now due to lower power usage but it's close, and the next-gen of both should make it interesting).
better to mine ethereum
For now and probably for a few more months. I'm looking further ahead though, when the mass influx + the announced "exponential diff mod" stuff will probably drive Ethereum to marginal on profitability - and of course the switch to PoS will kill it outright eventually (sometime next year IIRC).
ethpool is "semi-solo" payout method, ethmine is standard PPLNS type pool.
As far as I know any ethereum address should work with it - mine is pointing to the exchange I normally use for now, don't even have a wallet set up.
I don't think it waits on a block to be found to show your shares, but you DO have to have submitted at least one share before you start seeing stats - and it takes a while for the graphs to start showing anything as they're based on the 24-hour average (Ethmine anyway, I never tried Ethpool).
