Re: [19 TH/s] BitMinter.com [ASIC support: var diff, Stratum, GBT, rollntime]
I have a 3/31 Jalapeno that I did recently upgrade to 7 and I'm pretty sure by the time it gets to me I might be able to use it to warm a mug of coffee. That was a serious jump and we currently seem to be without WhitePhantom and CloudHashing 
As there are a few on Ebay now put some numbers on here http://mining.thegenesisblock.com/a/190e4d4536 (numbers for the 5.5 at list price and last months difficulty increase.)
At current difficulty increase a coffee warmer by March 2014. So I think that must mean that difficulty should stabilize before then as there will be no point anyone buying an ASIC.