No, IE7 isn't a virus, though it is a bit buggy sometimes. However, there is a real threat out there, and it's sitting in your inbox disguised as an Internet Explorer 7 Download.
The e-mails carry the subject line "Internet Explorer 7 Downloads" and appear to come from email@example.com. They include a blue, Microsoft-style graphic offering a download of IE 7 beta 2. Clicking the graphic will download an executable file called IE 7.exe.
The file is actually a new virus called Virus.Win32.Grum.A, and security experts were still analyzing it Friday to see what it does. Sophos PLC said it can spread by e-mailing itself to contacts in a user's address book. The virus tampers with registry files to ensure it gets installed, and it tries to download additional files from the Internet, said Graham Cluley, a senior technology consultant for Sophos.
Source: Network World