I would bet that there is a better chance all 4 #1 seeds make the final four than none.
The weaker the field of 64/5 the more likely more higher seeds (1-4 in each region) will move on to the sweet 16. Sure there probably be a 12 or 13 seed pull an upset, but that always happens every year.
Last year all the top 16 teams made it to the sweet sixteen except for two (Arizona as a 12 seed, and Purdue as a 5 seed was the only exceptions)
2008 was a little crazier, with only 11 of the top 16 making it to the 2nd week. You had two 12 seeds and a 10 seed make it to the round of 16.
2007, 11 of the 16 made it as well, but of the 5 that wasn't, none was double digit seeds and the highest seed to make it to the sweet sixteen was the 7 seed UNLV
I just think that this years tournament will be similar to last years with the higher seeds success. Just my opinon though.
James