Unfortunately, I can't see them upping the caps any time soon. After all, they offer more bandwidth if you're willing to pay for it, so I can see Rogers and Bell just pointing at the more expensive packages and going "Well if you really need that bandwidth..."
Yeah, they're just pinging you 2-3 dollars per gig, just like on their cellphone data plans. So technically you're free to use as much data as you'd like.
And in what I'm certain is a complete coincidence, Rogers lowers some of it's download caps: http://www.cbc.ca/technology/story/2010/07/22/rogers-download-limits.html