Breaking news (02/27/2009, first reported by MarkJ)
Support Statement for Visual Basic 6.0 on Windows Vista, Windows Server 2008 and Windows 7
"The core Visual Basic 6.0 runtime will be supported for the full lifetime of Windows Vista, Windows Server 2008 and Windows 7"
Note: MarkJ has posted an answer below (before my update), which should be considered as the official answer for this thread. Go upvote it ;)
(Initial answer)
Runtime should be supported for Windows 7, and not after, If I believe this Software Migration Expert blog entry (January 2009)...
I spoke to Paul Yuknewicz who is a Program Manager on the Microsoft Visual Basic team and who is quite involved with everything related to VB6 and its migration process.
Paul said and I quote: "VB6 runtime will be shipping and supported as a part of Windows 7, however there are no plans to ship it in future versions of Windows."
As stated in the same blog, the Support Statement for Visual Basic 6.0 on Windows®Vista™and Windows®Server 2008™, the Visual Basic 6.0 runtime support files will be supported until at least 2018 (Windows Server 2008 came out in 27 February 2008):
Supported Runtime Files – Shipping in the OS: Key Visual Basic 6.0 runtime files, used in the majority of application scenarios, are shipping in and supported for the lifetime of Windows Vista or Windows Server 2008. This lifetime is five years of mainstream support and five years of extended support from the time that Windows Vista or Windows Server 2008 ships. These files have been tested for compatibility as part of our testing of Visual Basic 6.0 applications running on Windows Vista.
I know this is about Vista, but if Windows Seven is more an evolution than a revolution, that may apply to Windows seven as well (nothing official though).
However:
The Visual Basic 6.0 IDE will be supported on Windows Vista and Windows Server 2008 as part of the Visual Basic 6.0 Extended Support policy until April 8, 2008
So, even though you will be able to continue using your Visual Basic 6.0 applications, sooner or later you will need to either fix an issue found in one of them, or add new functionality that is required by your business. And when that day comes, you will face the harsh reality that the VB6.0 IDE is no longer supported.
MarkJ suggests in the comments:
"you will always be able to run the VB6 IDE in a virtual machine so it wouldn't be catastrophic that the IDE isn't supported"
Indeed, you could fire an Xp session with your favorite old IDE in it ;) (even if, in this picture, it is launched from... an ubuntu session!)
alt text http://www.blogcdn.com/www.downloadsquad.com/media/2008/02/virtualbox-ubuntu.jpg