HS2 Ltd is the company set up to develop and promote the project. At this point, all you need to know is that:
HS2 Ltd is a company wholly owned by the Department for Transport.
Yesterday a job opportunity popped into my in box - unsurprisingly from the Guardian's jobs section. Following the link took me to this:
Head of Public Affairs
Salary: up to £97,398 + Benefits
The Head of Public Affairs will be defining the strategy and leading
HS2’s relationships with key stakeholders, the public and the media.
Closing date: 21st May 2012
Nice job! Over £100,000 for what is essentially a lobbying job - after all the "go ahead" for HS2 isn't a "go ahead" but the government's stated intention to put a bill before parliament to enable the project to happen. So the main point and purpose of this "public affairs" position will be to make sure that this happens - that MPs and Lords are suitably smoothed, that ministers don't wobble and that other parts of government such as the treasury don't nobble.
Despite stating they would stop the practice, this is the government funding an organisation so it can - in part - lobby the government.