This doesn't hide the domain completely, unfortunately. It can still be seen if the user digs deep enough. Those who find it may consider this even more evidence of a scam, and that would be a Bad Thing.
If this were all taking place within a single domain and you were using Apache, you could use mod_rewrite to hide everything to a point where even browsers couldn't get at the information. I don't think you can do that in a cross-domain manner, though, and if you're not using Apache then this doesn't help much.