No unistore has been used there at the time. Or frankly anywhere since then that I've seen. They had streamed all clickstream/logs/intelligence and ran massive amounts of analytics on it. Results would get used elsewhere in the stack to sell/target/run ads, provide inventory pushes, etc. They moved quite a bit of it if not most of it to DBX for Variety of Reasons [TM] specifics of which are best discussed over beers.