We are using Windows 2003 server with IIS 6.0 and thinking of migrating to Window Server 2008 with IIS 7.0 to host our .Net applications
Is anyone aware what are the benefits or drawbacks of it?
Answer
One definite benefit is the new "Integrated Mode" on application pools. This allows asp.net to hook into the pipeline earlier than was possible in iis6. Some of our applications use this to do url rewriting for files which was previous impossible with out adding a wildcard extension mapping to the asp.net dll.
Another feature that I've found useful is remote management. I believe remote management may have been available in iis 6, but if so it has been cleaned up and improved for iis 7. The basic idea is that you can allow an authorized remote user to connect to iis and manage almost every feature of iis.
Ssl host headers were also cleaned up in iis 7. You can now add ssl certs to the server rather than to a site. Certs are bound to sites and https host headers through the bindings dialog just like http bindings. This has the added advantage of making it very simple to quickly deploy one cert for multiple sites.
One (hopefully last) Edit:
Microsoft has released a tool for web deployment which offers migration tools for iis6 to iis7. If you decide to move ahead with it I strongly recommend downloading it (here) and reading the migration instructions here.
We went through the same process about a year ago and I have been very happy with the results.