I never tried hotlinking files before, I might give it a go with a .jpeg later tonight
As for "how easy" to point domain to .Mac, it depends on your domain tools, I was with some crappy site and it didn't support DNS(?), so I had to transfer over to Reg123 and do it from there, took 48hours for the domain to be refreshed, basically changed my domain's pointing to .mac's and through iWeb, you follow the steps and you'll be fine - almost fool proof (I'm kinda a fool in terms of domain/DNS/forwarding websites and using them tools.