Some chipsets have pretty good HD decoding.
AMD 690G:
http://www.scan.co.uk/Product.aspx?WebProductId=845045
Nvidia Geforce 8200:
http://www.scan.co.uk/Product.aspx?WebProductId=827893
So at this moment a system with an AMD CPU is the better choice. But if you prefer Intel you can go for the I-N73HD, it has HD decoding as well, but from a previous generation.