The music from Mega Man 10 is the strangest creature ever. On one hand, it assembles composers from each Classic Mega Man entry in an all-star jamboree. On the other hand, their contributions are perhaps some of the most boring tunes in the series, and it's up to the Wily tracks and beyond -- composed by the Inti Creates sound team -- to carry the remainder of the soundtrack. That's not to say the music is "bad," simply that you have to give it time to grow on you.
That said, there are a number of tracks from the game that I would consider among the best in the series. One in particular is "Solar Inferno," the theme to Solar Man's level, composed by Mega Man 3's Yasuaki Fujita. A high-octane, bass-heavy, thrash-influenced number, it's unlike any other Classic Mega Man song.
Patrick "NukaCola" Kulikowski covered this insane jam as part of his VGdrum project earlier this week, but I waited until the E3 stories started to die down before sharing it with the rest of you. His skills are getting better by the day, and this "Solar Inferno" arrangement may be his best work yet. By the 1:03 mark, he just kills it. It's not even funny.
VGdrum: Mega Man 10 "Solar Inferno" [Pixelitis]