First, there is a thread on the F150 Forums you should read.
The guy is using a 09 F150 w/5.4 to pull his 5th and a boat.
Interesting article - 5th wheel towing with F150- I am doing it!!!! - Ford F150 Forum - Community of Ford Truck Fans
Second, wait for a 2012 F150. Ford is increasing the payload on Super Crew from 1900 lbs to over 2400lbs at 29% increase.
I was going to buy a 2011 EB to replace my F250, but decided to wait for the 2012 which you should be able to start ordering by the end of August.
My weights- dry 7200lbs. Wet ~8700lbs.