I believe it's supposed to be available to "regular" (that is,
non-enterprise) users early next year.
Ah, here.
http://www.computerworld.com/action...ewArticleBasic&articleId=9002372&pageNumber=2
says, "Microsoft currently plans to release Vista to corporate volume
customers in November and make it generally available to consumers and small
businesses in January, at the same time as Office 2007."
However, I must be doing something wrong, because I can't get the overtype
ability to work in PPT 2007, either. Until someone can confirm one way or
the other, you might want to do the "test drive" so you can try it yourself
(this is much less painful than actually installing a beta -- it just runs
online over a Citrix server) at
http://www.microsoft.com/office/preview/beta/testdrive.mspx