I think the only good one has been HHH V HBK V Benoit. It was the 'first ever' triple threat main event match at Mania (or so I believe) for the World Title in the ME slot, and really just added to the hype of the match. Here you had Benoit, who was coming from the other show in between two guys who had a heated rivalry. The thing was built up fairly nicely (imo) because you had that background between HHH/HBK and slid Benoit into the mix.
Benoit didn't seem to lose any momentum from his win, as it was a big time match and he ended up making Triple H tap out (which was a first in it's own right, as well). So there really wasn't any lost momentum between the Rumble winner, and the champion still 'put over' Benoit.
Look at though, Rey/Angle/Orton - this one was poorly done. Putting aside the ENTIRE Mysterio "build" going into WM22, this match was awful! You had a champion, Angle, who was too good at the time for both men, and then you had Orton who was clearly supposed to have won the rumble that year, and a 'charity case' of Mysterio. The build was no of Main Event status, but instead that of a poorly written soap opera (and I mean that as if it were worse than some of WWE's usual crap).
The match was even worse! It was a god damn cruiserweight match filled with 'spots' like a double german suplex and what not, and resembled nothing of a WHC Match (lasting only 10ish minutes). That, and they completely disregarded the stipulations of an actual triple threat (apparently there WERE DQ in this match?...). To top this all off, they had Mysterio pin Orton to win the title - the first man obviously to win the title without pinning the champion! A poor, poor excuse for a triple threat match.
WM24 - Cena/HHH/RKO was a solid match. Good build to it all, especially with Cena being the rumble winner and HHH winning the title match. The match was good as well, but was a wee bit short in it's own right. Possibly the only semi decent follow up triple threat match since WM20. Again though, this one seemed too quick and had a few too many 'spots' for the guys involved.
I fear this years triple threat will be the same - they'll use show for some big spots, and will focus on it being a spotfest more than what it should be - a triple threat. They won't push this match like the Benoit/HHH/HBK match, push the superstars for that (imo) preferred 'gruelling match', instead they'll shorten it and put in some cool tricks with Show. As good as this will be to watch, it won't be a 'classic', and that's what I'd prefer to see...