There is a couple of things that could play a role. Such as: - if the phone is brand new, new types of batteries like those used nowdays on phones & laptops need a few cycles to gain their full capacity - several DBs (such as for thumbnails, contacts etc.) need lots of processing power to be build fully and they are put in the background at low priority that could take few days to complete. If you added large sets of data such as pictures, music etc. in a fresh OS this is quite significant. Obviously, i might be completely off here especially since you are a power user.