This appears to be a confusing topic. Why when I have a Google Apps (Enterprise no less) do I not get a standard Google Account with it? Just to use iGoogle we have to create an additional account (and sign in) then it’s a silly process to get the iGoogle home page to respect the mail and calendar services from my Google Apps accounts.
Google: Sort this out! Just make Apps users have accounts for all the other Google Apps. This duplicated account scenario is just silly from an organization your size.