Razor is prettier (and is new therefore cool).
Webforms is something I am already familiar with.
Naturally I would unquestionably go for the new thing to learn - Razor. But I have heard of two disadvantages that worry me:
So what are the advantages of Razor over Webforms view engines when using ASP.NET MVC 3?
This has already been addressed by the following question: Does Razor syntax provide a compelling advantage in UI markup?