I missed this one. On 19 June 2007 a report was published by the group "Green Gauge 21" suggesting that a high-speed link from London, St Pancras to the North of the UK is being considered. It would cut journey times from Birmingham to London to 45 mins and Paris in 3 hours. The route would be called High Speed Two (High Speed One being the channel tunnel rail link from St Pancras to the chunnel). There should be further announcements next month (I guess July, but you never know), and is probably going to be part of a wider transport announcement by the new Prime Minister (who is known to favour TGV style system rather than Maglev and could well announce the cross London project in time for Olympics). If there was such a project going ahead, it would probably reach Scotland in 2020, cost billions (inevitably) but if they start now then it could well improve transport to London for the Olympics in 2012 (maybe).
The funny thing is that this would line would be the second high-speed link in the UK, cross the entire country, have speeds of up to 300 km/h and even put Germany to shame – it effectively has only two 300km/h lines and the prospect of building more depends on political will which is not guaranteed). I would love this to happen because the UK sorely needs an alternative transport system (compared to driving or flying) and should have a high-speed system to be proud of. We will not hold our breath on this one, but you just never know.