According to a report on the BBC website, the sale process of the Chiltern Railways franchise by Laing Rail appears to be drawing to a close. Formal approval is required from all and sundry, but I reckon it'll happen.
In theory nothing much will change- the trouble is that Chiltern Railways are highly regarded and generally thought of as being just about the best reailway company. 'Best' costs money (or good management) and these things are often in short supply after a corporate takeover. We'll just have to see how things shape up.
By the way, the Central Line is an absolute bloody nightmare at the height of the morning peak. No problems with how it runs, there are just too many people. Roll on the Olympics.