I found a great trip report from allears:
http://land.allears.net/blogs/guestblog/2011/05/star_wars_weekends_2011_1.html
this will give you an idea on what to expect.
Now I'll try to explain how the autograph FP's worked Last Year:
They have the lines set up outside the turnstiles on the far right. People do camp there overnight, I've never had and always got the autographs I was looking for. I usually get there around 5:30am for everyone, the year I got Dave Prowse (Darth Vader) I got there at 4:30am and was on standby but still got the autograph.
Everyone in your party that wants an autograph and/or meet the celeb must be in line. They scanned your park ticket, put a wristband on you and give you your fp time to meet the celeb. Then you go into the park.
For people that wanted more than one fp (For example if you wanted to meet Ray Park and Daniel Logan) you got your first fp's then you had to wait in another line for 2 hours and if there were fps or standby left you would get a second wristband and fp.
Now alot of people got angry with this new system, you see before,you could line up get a fp's and then get in a second line right away and grab another fp/standby. People that were in line from the night before could meet 3 celebs in one day. Disney was trying to give opportunity for more people to meet celebs by enforcing only 1 fp/wristband per 2 hours.
Last year we didn't have any issues since we only got autographs from James Arnold Taylor, Ashley Eckstein and Matt Lanter for the 4 weekends.
If you want to try and meet multiple celebs in one day your first fp should be the visiting celeb (for example Ray Park) then you can go around and wait 2 hours and grab a fp/standby for Ashley or James since they're there the 4 weekends these will be easier to grab.
This is all according to what happened last year, we don't know if DIsney will continue the wristband thing or go back as to what it was before.
Last year there was alot of drama about this issue. I hope I explained it well so you have an idea on what to expect. If you have a kid that wants to meet a celeb he must have a wristband and fp. Anyone who doesn't have a wristband/fp will not be able to meet the celeb even if you don't want an autograph.