The big issue is that Telus & Bell have been saying that they've had a "3G" network for quite some time (with their CDMA handsets that use EV-DO Rev. A for data connections). Now that they are using HSPA on the new network, it is leading to some confusion if they just label it "3G" as it really is.
Bottom line though: If the phone supports HSPA/UMTS/WCDMA frequencies of 850MHz and 1900MHz you are good to go. Of course, a Telus rep would want you to buy the phone from them as that's where they make a commission (handsets and long-term contract renewals).