The Toyota Prius is front wheel drive (FWD). It is no worse than any other FWD vehicle.
The OE tires are OK for the first winter season, but once worn, will kick in the overactive traction control... If you replace the OE Goodyear Integrity tires (found on non-Touring NHW20 Prius) with a more aggressive "all-season" M+S tire, or preferably use a set of snow/winter tires seasonally, then the Prius has wonderful handling in winter snow and slush.
Mostly information for the older NHW11 design, but:
http://autos.groups.yahoo.com/group/..._001007996330/
Just be aware that you have only about 5" of ground clearance, so don't expect to be plowing the roads with your Prius - wait for the trucks to come out and do it for you...
I'd suggest that you ask actual owners, rather than the random assortment of people here on Y!A. (I've had my Prius for over 8 years now, but I think I'm a rare owner on Y!A...)
Check the message archives first before asking on:
http://autos.groups.yahoo.com/group/toyota-prius/
http://autos.groups.yahoo.com/group/Prius-2G/
http://autos.groups.yahoo.com/group/2009-Prius/
http://www.priusonline.com/
http://priuschat.com/
The Prius is typically the 3rd or 4th best selling model car in Toyota's fleet in the US, so you'd be among good company!