On Windows 2003 (32 bit Standard Edition with 4GB of RAM) we would host around 1200 sites on a single server split across say 4 application pools. This has worked well for us for a number of years.
IIS7 seems to favour creating a separate application pool for each site and I am lead to believe that IIS application pools are somehow tuned better for this purpose.
Has anyone in the community had experience of this approach with large numbers of sites on a single server?