Right now, you see no results for that househuntingwithtony query, because nothing is tagged with that (a good thing, since you only want people seeing what you've selected), but if you use that tag, you'll see your content appear there.
As an example of a tag that is in use, I have tagged photosynths and panoramas which I shot with my Samsung Focus with the keyword windowsphone.
This isn't a unique tag, however I do appear to be the only one using it right now. For my purposes, I do not mind if other people tag their synths and panos with the tag, because although I have used it to cluster content that was actually shot with a Windows Phone, I wouldn't mind if someone else used it on their photos *of* a Windows Phone. If other people want to add theirs, I'm happy with that.
The only danger is someone else stealing or accidentally using your tag, so, again, it is to your advantage to make it unique to your content.