It's very true indeed. Windows 7 is expected to be released in 2009-2010. About a year from now we can expect a beta release. That's the semi-official plan at least. I bet there will be delays. Rememer Vista was released in 2006 and new OS every 4 years is not unusual. Windows XP was released in 2001, Vista late 2007. MS are trying to release versions a bit faster now. http://www.thebetanews.com/is-windows-seven-scheduled-for-a-h2-2009-release/
Everyone is correct, they are not releasing Windows 7 yet. It won't be released for a few years since Vista just came out. Microsoft is probably working on it, but would have beta testers until one or two years have passed. Just look at the gap between XP and Vista.