SATA III in my opinion will still be around for a long time after SATA express takes off, might even stick around longer than SATA II. Same thing with DDR3 for consumer markets. Aside from niche markets (Super-enthusiasts, Servers, Workstations, people with more money than sense) there is no need for faster interfaces. Server market is going to be big but outside that, for the next 2-4 years unless SSDs drop down significantly in price/GB I can't see SATA express going mainstream. There is no need, it would be more expensive for OEMs and the performance benefit people would see would be marginal if any for day to day tasks.