Mothers Day 2005 was on May 8. I know this because I arrived on May 8. If room occupancy and park crowds were especially high that day, it might not have been as much Mothers Day as it was the fact that the 50th Anniversary Celebration began with huge fanfare and excitement on May 5, 2005. A lot of Disney fanatics went to WDW that weekend just to be there near the beginning of the 50th Anniversary Celebration. There were new things at WDW, such as Soarin' at Epcot and the new car/stunt show at MGM, etc.
Otherwise, it wasn't "badly" crowded that week (May 8 - 14). I remember that on Sunday night (May 8) we went to MGM and before the evening EMH started we walked right into Muppetvision 3-D, waited less than 5 minutes for Star Tours and Playhouse Disney, and less than 10 minutes for Rock n' Roller Coaster. I didn't have time for ToT but it was also only like a 10 minute stand-by wait.
Monday May 9 had some decent-sized crowds at MK, but with a decent home-made touring plan we accomplished everything we wanted to; about the longest non-FastPass wait we had was 40 minutes for Dumbo, right at lunchtime (don't ask how we got stuck doing that then rather than first thing in the morning!).
The Tuesday of that week (May 10) we did the front half of Epcot -- Mission:Space and Test Track both had 45 minute stand-by waits by mid-morning, but again, Fastpass and a good plan made things managable. Soarin' was HUGELY crowded, but it had just opened (I swear the posted FastPass return time was for a different time zone). That night at MK, we walked right into Haunted Mansion, and people without ADRs (then-called PSs) were waiting only about 15 minutes for character dinners at Crystal Palace (where I had a PS).
And the Wednesday night of that week (May 11), which was an EMH night, we walked right into PoTC and there were also NO LINES at BTMR and Splash.
Thursday (May 12) was moderately crowded at AK, but again, FastPass and a good home-made touring plan made everything okey-dokey.
Friday the 13th, of all days, was the most crowded day we had. At mid-afternoon, I think the stand-by lines for Splash Mountain and Big Thunder Mountain Railroad were something like 70 minutes, and it was sometimes difficult to walk around in that general area of MK. It was our only "uncomfortably crowded" day at WDW.
We didn't do any parks on Saturday the 14th, just DTD, which was no problem at all.
I know, I know, more information than you wanted, but I hope it helps. And by the way, I made my touring plans on-the-spot, on-the-fly. I didn't have any touring plans written down, but like on the bus going towards a park I discussed things with my wife and suggested what we should try to do. I was able to do this due to months of loving and exhaustive research using Birnbaum's, The Unofficial Guide, and some message boards, including this one. I had all the information I needed to make effective decisions, but I was able to be fluid enough to deal with whatever came up (rain, unexpected long lines, bad moods

, etc.).
ENJOY WDW!!!
-- Eric
