HDMI does have autoswitch facilities but it is not as simple as scart you need to make sure that your TV supports it as well I think most devices with HDMI 1.3 do and to make it even more of a headache all the manufactures have a different name for it, Sony call it Bravia Sync Samsung call it Anynet.
It allows you to control all your HDMI enabled equipment, so you can turn on your TV and control the HDMI equipment with the same remote.
Don't ask me how to turn it on or configure it as I just use a Harmony remote which is far more flexible. If your TV has a HDMI 1.3 it is more then likely has this feature.
Here are a few links for your reading pleasure
http://www.cepro.com/article/inside_...ntrol_feature/
http://www.hometheatermag.com/hookmeup/208hook/
The HDMI Wiki page also has a little about HDMI CEC
http://en.wikipedia.org/wiki/HDMI