Hmm, I think Michelle's jumps while sometimes UR'ed or flutzed (which, mind you, wasn't as much of a big deal until the IJS, so arguably she played to her strengths if she wasn't getting deducted), she had a quality of finishing them that didn't disrupt her performance. Slutskaya's errors, as Peggy said, looked sloppy, which detracts from the performance.
Don't get on Michelle's case if you don't also get on the case of the number of World Champions before her who flutzed and UR'ed but still got away with it. At 2001 Worlds LP, arguably Irina lipped her flip, and she certainly flutzed on her lutz.
And yes I said Michelle's 3-3 was "slightly underrotated" as in it would have got the < call, as you yourself said she would. It wasn't under-rotated so much as a downgrade. Her flip would have gotten a < too, but not a <<. Also, I don't see how her lutzes could have gotten <? Both looked within 1/4 turn when her skate hit the ice. The judges gave her 5.7 and 5.8 for that. I think the UR on the flip and toe loop would account for that. Slutskaya on the other hand also got 5.7/5.8/5.9 when she was < on her salchow-loop, and << with a step out on her lutz-loop. Similar errors as Kwan. Really she was given 5.9 for attempting the 3-3's, not actually landing them. But then Kwan won on artistry (which made sense). So I think the competition was correctly called. It's remarkable that Slutskaya attempted two 3-3 but attempts only get you so much credit.
As for Hughes, even though her 3-3 were UR, the rest of her program was flawless when Kwan and Slutskaya both had significant errors. Hughes' errors didn't affect the "look" of the program either as they were subtle UR and not glaring falls or step outs. It was a very good thing for figure skating -- especially with the 2002 scandal -- that Sarah Hughes won the gold medal in 2002. Many wanted Kwan to win, but when both she and Slutskaya erred and Slutskaya performed better than Kwan, the judges had no choice but to put Sarah first. People knock Sarah for underrotating her 3-3, but at least she didn't play it safe and still make obvious errors as Kwan/Slutskaya did. If she had done double loops instead of triple loops, she still would have had a cleaner program.