[TorontoColin]

If you're purchasing on contract take a look at both Telus and Bell's smartphone plans. A better plan might be enough to make your decision for you. Also note that Rogers will soon be carrying the Samsung Captivate (another Galaxy S phone), so you may wish to consider them. I always recommend choosing the phone last, plans and coverage are more important long-term than having the shiniest handset.

Please see this thread for some feedback on the Desire.

And this thread for the Galaxy S Vibrant.

This thread also may interest you as it has some handset comparisons.

Personally I'd prefer the Desire because I like HTC Sense much more than Samsung's Touchwiz skin, but if you like the increased size and improved screen of the Galaxy S then that might be a better choice. Both are definitely fantastic phones.

 

[TorontoColin]

Call Bell, if you've been a customer for six years maybe they'll offer you a retention deal. Then, take that offer to Telus and see what they say.

Both the Vibrant and the Desire would suit your needs well.