There's been considerable, and at times heated, discussion about the technical quality of the BBC HD channel, primarily related to changes in the Freesat feed (lower bitrate, change of encoder) - the general tenor of the discussion being that these have been downward steps in quality.
A group of the leading contributors (to the BBC's HD - since relocated to Internet - Blog) were invited to meet the BBC group they've been arguing with, and participate in technical tests. You can read a first report of their meeting at http://www.bbc.co.uk/blogs/bbcinternet/2010/06/picture_quality_on_bbc_hd_a_vi.html
It's worth noting the several references to tightening up on production companies to meet the specs (ie in camera / coding choices). We'll see how this develops.
What they don't talk about is the choice of transmission standard for satellite feeds of HD - in the UK we use a standard known as DVB-S which is an MPEG2 transport stream. Elsewhere, in Germany for example, DVB-S2 is the standard. As you'd expect from the numbering, it's a later (and improved) development, and can include MPEG4 (aka AVCHD) streams. It would appear that Sky and Freesat are moving towards DVB-S2 - and I'd assume that any receivers marketed as 'Freesat' will be dual capable. If you want to see the results, the two German HD channels (Das Erste HD and ZDF HD) are currently transmitting in the clear on the Astra satellite system (19.2 E).
