RDP is more of a service application, probably why it's not in home edition. It's going to be targetted at end users who want a cheap system with cheap software, and having services like this constantly running in the background could cripple the system.
yeah, but come on - it couldn't be that hard to include. I use LogMeIn and that works great (and it runs in the taskbar all the time), but sometimes it's annoying to install. I'd rather use RDP and just be done with it.