Getting Content by Guid in v7

Questions
1

How can I get a node by its Guid in v7.1+?  We'll be using Courier down the road, and I want to avoid issues with referencing nodes by their int id in Razor.  For example, instead of doing this:

var menuRootNode = Umbraco.TypedContent(2363);

I need to do this (but Guid isn't a supported argument):

var menuRootNode = Umbraco.TypedContent(someGuid);

Referencing this old post re: avoiding the int IDs when using Courier.

http://our.umbraco.org/forum/umbraco-pro/courier/28391-Courier-transfer-of-content-node-has-two-different-IDs

Thanks.

This is a companion discussion topic for the original entry at https://our.umbraco.com/forum/59288-getting-content-by-guid-in-v7