ASP.NET MVC Preview 5 introduced a new
[AcceptVerbs] attribute that you could use to indicate which HTTP verbs an
action method supported.
In preview 5 you always specified verbs using
strings. We still support this with the beta, but have also added support for common verbs to be specified using a strongly-typed enum mask. For example:
Figure 19

Today's beta release also no longer requires
that you specify [AcceptVerbs] on both actions in scenarios like above.
By default ASP.NET MVC now looks for an action method that explicitly supports the incoming http verb - and if one is not found will use the action method that
doesn't have an explicit verb specified. This saves some typing for
common GET/POST scenarios (you no longer need to decorate the GET method).