Really? I didn't realize that. I was under the impression that Wind Waker itself didn't actually sell that well and that this was doing far better. Got anything I can read?
Also, I kind of liked the TP soundtrack but it would have been far better for me if the dungeon themes had been more memorable. I mean, some (most) of them were basically just background noise and not music at all. Ocarina's dungeon themes were fantastic, especially some of the later ones. Anyway, I did like a lot of the other music though.
Incidentally, I haven't liked a trend that's been done a few Nintendo soundtracks as of late. They make a theme that's easy to remember and then incorporate it into or just feature it as the melody in EVERY single song in the entire game. Think New Super Mario Bros, now Twilight Princess, Super Mario Sunshine, maybe even Wii Sports, etc. I mean, sometimes it helps to make a soundtrack more memorable and catchy, but sometimes I'd really prefer they just have a lot of catchy themes instead of one with minor variations. Sometimes it works, too, but you know, I really didn't need to hear that same Hyrule Field theme again in the Gerudo Desert and so on.