Discuss. 
If you consider 1st gen cryptos to be Bitcoin, Litecoin, PPC, NMC, XPM...
The next generation with potential IMHO are the ones using new protocols, financing mechanisms, trust gateways, custom exchanges:
- MSC Mastercoin, using "Exodus" protocol on top of Bitcoin to create a virtual trading exchange, has lots of BTC funding
- Ripple, XRP as a script IOU to trade between currency on trusted gateways, has big venture capital funding
- NXT, different distribution model, custom exchange, has some growing pains
- Counter Party, "burning" Bitcoin for XCP in peer to peer trading
- Colored Coins, not sure of status
A few others with promise in the weed of Alt Coins that I see:
- Digital Coin, DGC, one of the few from earlier days with little or no premine, a steady, safe reliable coin, worthy of investment
- AnonCoin, ANC coin has stealth innovations, untraceable from blockchain, mining, exchanges to your wallet
- Philosopher Stones, PHS pays out 50% annual interest, does not require huge hardware to mine/maintain, just turn on laptop
