That's the year we'll make contact, and not before.
A Microsoft source confirmed to Neowin that Windows 7 would not be released next year and that it is still on track for 2010, already disclosed earlier this year on Microsoft PressPass and Microsoft Road map charts.
Bearing in mind that 2010 is just a little under a year and a half away, it's unreasonable to think that something would be released in between; however we can speculate that SP2 for Windows Vista will come before then and may introduce some new features making the upgrade from XP worthwhile. Pure speculation of course!
Link: Windows 7 May Come 'in the next year or so' (Posted on 5th April 2008)