Aimee Mann, if she's the same one I'm thinking of, was in a pop band called 'Til Tuesday that had one and a half, maybe two hits sometime around 1987 or so. She had a solo album out later, I believe. I don't remember the names of the 'Til Tuesday songs, but they were MTV favorites. Mann also did a guest vocal on Rush's 1987 album. I think she's Canadian. It may not be coincidental, then, that she's opening for Bob in Montreal.
... Aimee Mann (this is the correct spelling) was the lead singer/songwriter for a mid-'80s sort-of-new wave group based out of Boston called 'Til Tuesday, best known for its 1985 Top 10 hit "Voices Carry." They released about 3 albums before fizzling out late in the decade, aroudn the time Aimee's affair with cult songwriter Jules Shear also fizzled (much of this was chronicled in her music).
Aimee Mann has resurfaced in the past few years as a pop singer-songwriter to be reckoned with, with two solo albums on Imago Records. Her songwriting and arrangements are very Beatlesque -- indeed, her solo debut, 1993's "Whatever," combines Byrds-like folk-rock (Roger McGuinn even reprises some ofhis old riffs on the album) with Sgt. Pepper-style production. Her latest, the recently released "Im' With Stupid" is said to be as good or better -- I haven't heard it, but if it is really that good it's definitely worth checking out.
Played on the soundtrack for the 1999 movie "Magnolia".