That's not true. You can actually get BlackBerry service through Rogers Wireless on a month to month basis with no contract. If I am not mistaken their combined BlackBerry voice and data package's require a contract but Rogers does have voice plans and BlackBerry data plans that are on a month to month basis.
BlackBerry Plans are available on a 1, 2 or 3 year service agreements only.
*The $25 BlackBerry Service Plan is only available as an add-on to a Rogers Wireless Voice plan subscription.
If there is some way round this, then getting blackberry from rogers makes sense. I will want voice as well anyway, but was planning on just getting another month to month contract for that and using my Motorola Razr from the UK as well.
I did oringally provide the URL for this from rogers website, but am not allowed to post URLs yet it seems.