I'll play.
one year out:
1) BTC
2) PPC
3) LTC
4) NXT
5) PTS
6) XPM
7, 8, 9, and 10 will be DACs that spawned from the Bitshares toolkit.
Now, 2 years out:
1) PPC
2) Bitshares-PTS
3) BTC
4) XPM
5) NXT
6) Unknown DAC
7) Unknown DAC
LTC
9) Unknown DAC
10) Unknown DAC
10 Years out:
1) BTC
2) Random altcoin
3) Irrelevant.
Bitcoin won't lose its spot unless something really bad happens, like a 51%.