We were there 12/3 to 12/10. The Sat. and Sun. of parade taping at MK were both MK days for us, and we would do it again. Our experience was that Main Street, of course, was inaccessible -- CMs routed park-goers through the shops along the left-hand side (facing castle) so that we could come out at Caseys and enter the park from there. From about 3 to 6, Fantasyland was a zoo -- but we had very short waits in Frontierland for BTMR and SM, and Toontown was also very easy to negotiate (no problem saying hi to Mickey!) during that time. Tomorrowland was about half-way between the two in terms of crowds. We think that many post-parade people experienced the Fantasyland crowds and decided to leave -- Sat. night we came out from dinner at CRT at about 7:15 or so and found we could walk on, basically, to any rides (although overall the longest waits (20 mins?) were still in Fantasyland.
Bottom line: unless Fantasyland is your only MK destination, don't let the parade taping deter you!