[three west]

on verizon's MR1 with sense 2.1 mine would do every 3 hours. I added the custom .cab to get it to download once an hour. And yes, it does it any time the phone is on then.

Now with VZW MR2 and sense 2.5 there's an actual setting. I have it set for once every hour, but I often notice that it hasn't updated within the hour.

So that's a long round-a-bout way to give you an answer of maybe...