[Ken Case]

Yes, that's correct: at the moment, the desktop interface doesn't have any way to specify the geographical location of a context the way the iPhone interface does.

If this is something which would be useful to you, please let us know! But please also understand that right now we're trying to get 1.1 stable as quickly as possible so we can get it out of beta—making us reluctant to add new features. (In other words, it might have to wait for 1.2.)