At this stage almost anything can happen, Sunderland I don't think got the right manager to turn it around, Palace have improved significantly already but they could get 10 times better and still lose most of their games, give them a bit of time.
West Brom/Swansea both started off the season with last years woeful form but after hte first 3-4 games have picked up significantly.
Villa/West Ham/Norwich certainly aren't playing well and Cardiff will probably be in the relegation fight.
Thing is Fulham were 15th before today, 16th now(with results as they are), but they've already played and beaten Sunderland and Palace.
Fulham have a lot of genuinely very good players, plenty of decent ones, I think firing Jol and a half decent manager and midtable comfort is very easily within that teams capability.
At this stage I would say team/squad wise Sunderland/Palace/Cardiff are favourites to go down, with Norwich not far off, not enough goals in them. Fulham have probably the strongest "relegation battle" squads, with a manager who doesn't have a clue how to get the best out of them.