This is an interesting one - I have IE 7 installed on all my machines except my SBS 2003 server and the reason for it not being on there is because I like to have an IE6 hanging around for those sites where I have no other option - and browsing on the server (sorry Susan) is something I really, really try to avoid, so the site must be important enough to me, trusted and not need any java etc before I will consider using it.

Anyway, that means that 7 PCs in the house (counting the 2 work laptops) are IE 7.  I have not found a site that does not work yet, although some like the Live Spaces photo uploading tool is a bit of a pain in the bum to get working (you need to run as admin in Vista).

IE 7 reaches 100 million users

Web browser now second only to IE 6 in terms of usage in the U.S., Microsoft announces.

More than 100 million people have installed Internet Explorer 7, making it the second most used browser in the U.S., trailing only its predecessor--IE 6, the software maker said Friday.

"I'm pleased to report that on January 8, we had the 100 millionth IE7 installation," Microsoft Group Program Manager Tony Chor said on the IE blog. "However, even more important than installations is usage. According to WebSideStory (the company we use to measure browser usage), as of this week, over 25 percent of all visitors to Web sites in the U.S. were using IE7, making IE7 the second most used browser after IE6."

Microsoft said it expects IE 7 usage to grow as the company completes more localized versions, offers it up to more Windows XP users through Automatic Update and releases Vista to consumers at the end of the month. The final version of the new browser has been available for download by XP users since October and is also built into Vista.

Source: IE 7 reaches 100 million users | CNET News.com