Thanks to a leak from The Verge, Microsoft staff are said to be testing early versions of Windows Phone 8 running on a 1.5GHz dual-core Snapdragon S4 processor, or the MSM8960. "At least one" phone would have the combination sometime later in the year.
Sprint was also said to be interested enough in Windows Phone 8 that it was courting Nokia about the prospects of an LTE-based Windows Phone 8-powered device. Sprint has skipped most newer Windows Phones since the HTC Arrive last year, and might not want to go back without there being an LTE-powered device to keep them competitive.
Microsoft's jumped into a minimum of a dual-core processor should help them along, but Microsoft have always used Snapdragon-based processors in their Windows Phone chassis spec, so this shouldn't change.
I'm quite excited about Microsoft this year, with Windows 8 and now Windows Phone 8 on its way, it should be a good year for MS!