This week is a “CMS week” at CERN, and talks are available here. The plenary talk discussing the LHC status has:
If all goes well the machine should be cold by 1 June, and protons could be injected by mid-June. Use this information for laying out our schedule…
Poking around the LHC website, lots of other information is available. A draft general schedule from last week can be found here. It has cooldown of the last sector (4-5) ending in mid-June, and powering tests on-going at several sectors until mid-August. Plans from last year for commissioning the beam envision 30 days with beam to go from first injection to usable 7 TeV beams, with an estimate that this would take 60 calendar days. So, most optimistically, it looks like mid-late October is the earliest that 7 TeV collisions could be happening, right around the date of the official inauguration: October 21. More realistically, this may very well take until early 2009.