So iOS and WP7 handle permissions pretty much the same way Android does?
Pretty much. No OS is totally secure, of course but there is more limited permissions with both iOS and WP7, than Android. You take the good with the bad with everything. It's always a trade-off.
One problem is those whom just assume that they can keep pressing allow, and them boxes mean nothing and are a nuisance. The other problem (perhaps maybe down to Android's popularity, or because it truly is more insecure) is that there has been times when these security measures have been bypassed on Android.
I don't reasonably believe that nothing will ever hit WP7, because it's certainly possible (even highly likely) something could. As the OS gets more popular, there will also be more interest. As people find ways to give more access to the OS, there will (out of their efforts) come the possibility of malware. We don't know.