I noticed a tag wiki appear recently that I'm fairly sure misapprehends the subject, ahem, area. asp.net-mvc-3-areas is now defined as
ASP.NET MVC and its related flavors since 2007 by Microsoft. It has come up MVC4 and its still evolving...
I'm not an MVC dev, but I'm pretty sure that this tag covers the use of Areas in ASP.NET MVC, and not the whole "area" of ASP.NET MVC.
asp.net-mvc-areas (No version, just plain "areas") had no wiki, so I added one, to the best of my abilities.
I think asp.net-mvc-3-areas should be a synonym of asp.net-mvc-areas. The former has 106 questions and the latter has 176. More importantly, I don't see any evidence that ASP.NET MVC 3 deserves its own Areas tag. Not my domain (and thus I can't suggest the synonym myself), but it's possible that Areas was introduced in ASP.NET MVC 3. Regardless, I think the more general tag wins out.
(At minimum, I'd want to delete the incorrect contents of that tag, but I don't think mere mortals can do that)