We need two things - DVB-T2 and a MPEG-4 decoder. The MPEG-4 decoders have recently started showing up in recent Panasonic sets due to Ireland's use of MPEG-4.
I don't know when to expect DVB-T2 - it is still very much in testing and we may see freeview boxes first and TVs later. I would like to see it sooner than later - I could do with replacing a couple of my TVs and I would like to make sure they are compatible. I think it might be the case of either 2010 or 2011 models.
The old freeview system may be shutdown (in several years) and replaced with all DVB-T2/MPEG-4.
The very first Freeview HD tuners are reaching the early testing stages now and, if all goes according to plan, the very first models should appear at the end of the year. Like anything new, these will be expensive. Higher volumes will follow early next year. The main Freeview HD launch will be aimed at the World Cup.