Will Windows 7 arrive this year or next? Last week's "accidental" Windows 7 Release Candidate download page, dated May 2009, and repeated leaks to the Web of Windows 7 builds are strong indications that we'll see the next manifestation of Windows in about two months. Microsoft has not confirmed the projected May delivery date and the Windows 7 RC download page is now gone (click here for a captured screenshot). But a late-May release candidate would mean cutting it close for a final release before the back-to-school weeks of late summer. That leaves us with the more important 2009 holiday season, which despite the dismal economy, is something Windows 7 can't afford to miss.Here are three reasons why Microsoft is likely to have Windows 7 locked and loaded on computers before the holiday rush.Back to School Timing Would Be RushedEven if the Windows 7 release candidate does arrive in late May, that may be too late to have Windows 7 finalized for the pre-Labor Day back to school crowd, given all the changes Microsoft has made to Windows 7.Microsoft Watch blogger Joe Wilcox wrote that "four to six weeks minimum" will be needed for bug and application testing because of all the user interface changes made between the public beta and the upcoming release candidate of Windows 7.The next logical time for a release is for the holidays. Veteran Microsoft blogger Ed Bott writes that if the release candidate is in May, Microsoft will have time to do testing before releasing to its OEMs in late July, RTW (releasing to Web) in late August, and then doing a retail launch in late September. Bott writes: "If OEMs get code in July, they can have systems ready to deliver to customers in September, maybe even with a simultaneous retail launch ... holiday sales are crucial, and a September release allows for a full-on marketing blitz for the fourth quarter."Microsoft Keeps 'Accidentally' Saying 2009Last week's allegedly accidental Windows 7 RC download page is the latest in a series Microsoft slip-ups hinting at a 2009 release of Windows 7.Last October, Jerry Shen, CEO of Microsoft OEM Asus, said in an interview: "In the second half of next year we will put Windows 7 on Eee PCs."Also in October, Microsoft said on its WinHEC Web site that, "There is not another WinHEC planned before Windows 7 is released." WinHEC is scheduled for early May 2009.At the WinHEC conference in early November, Microsoft Director Doug Howe showed a slide saying that the Vista Velocity program would go through next spring and then continue with Windows 7.\n\nHe was then quoted as saying, "Definitely the holiday focus is going to be on [Windows] 7."January Release Will Remind People of VistaReleasing Windows 7 in the first month of a new year could bring back memories of a certain other Windows OS infamous for missing the holidays and launching in the new year. As everybody now knows, compatibility problems and memory hog gripes marred Vista's launch, resulting in negative perceptions that remain today.Any comparisons to Vista \u2014 even for something non-technical like a release date \u2014 could hurt Microsoft, considering that Vista seems stuck with one of the worst reputations of any version of Windows.Microsoft unmistakably wants to differentiate the two OSs (even if they are both based on the same code). Missing the holidays and releasing Windows 7 in January would be the exact route it took with Vista in 2006\/2007.