I didn't know Hive Tips were working already! I read a team was working to implement it, but they moved fast. :)
By the way, on Hive (not on Twitter), you can also tip bitcoin, litecoin and dogecoin (or rather their Hive-engine pegged tokens: SWAP.BTC, SWAP.LTC and SWAP.DOGE), via PeakD. From what the guys talk, this is only the beginning. But you have to enable them from your wallet, Hive-engine tab, and have some in your account.
Oh for sure. I think Peakd started something huge here and Hive Tips is just the next realization of this...Big things when we pay it forward :)