I caught most of the Toronto show on TV live and watched quite a bit of the highlights/re-broadcast of other cities from the internet.
Bryan Adams, Bare Naked Ladies, Neil Young, Madonna, REM, Will Smith, Destiny's Child, Kanye West, Sarah McLachlin & Josh Groban, Jay-Z (I haven't seen a live performance yet where I liked how Linkin Park [mostly Chester] sounded... even though I love their CDs.), all did fine by me (sound wise).
There's quite a few artists out there that sound horrible live or in a concert setting.