I only heard this cover of Little Red Riding Hood for the first time recently and am so disappointed there isn't a full version of this song! All that was arranged and recorded is heard in the ad. (Argh!)
Note: The 7Up commercial itself (from 2000 I think) is suggestive, as you would expect in any modern update of LRRH, and Red herself is, er, rather assertive. Considering she's being stalked by a wolf, I'm OK with it but not everyone may feel the same way.
From the comments:
Rosnick Mackinnon was the music house that did the arrangment and used session musicians to record. Vocals by an actress, but not the one in the spot.
In case you didn't know Amanda Seyfried (star of the recent Red Riding Hood movie and playing the daughter in the movie musical version of Mama Mia) also covered this song recently. You can hear that HERE.