i just watched my tivo'ed SNL. the second song, i didn't hear her voice at all. i'll have to watch the video. in the first song, it was also painfully obvious that she was lipsyncing because: (1) your voice doesn't stay that constant when you're doing your weird jumping/dancing thing, (2) it sounded EXACTLY like the radio/album version, (3) she messed up several times.
i'm glad absy pointed this out, otherwise i would have just fast forwarded through her songs, like i usually do with musical guests. at the end of the show where they come out again, she apologized and said, "my band started playing the wrong song." female dog. don't blame it on your band. if you weren't lip syncing, you could have just started singing what they were playing. ugh.