Here is a server header check from SEO Consultants:
#1 Server Response: https://www.google.com/ig
HTTP Status Code: HTTP/1.1 302 Found
Content-Type: text/html; charset=UTF-8
Date: Fri, 26 Feb 2010 08:29:08 GMT
Redirect Target: http://www.google.com/ig
There are several complaints about not being able to access the secure version of iGoogle at the Google Web Search Help forums. Paul from Google explained why this is the case. In short, the gadgets on the secure iGoogle were not always secure, which led to confusion. Here is the detailed explanation:
As you noticed, we've recently started redirecting any users who attempt to visit an iGoogle page using "https" to an "http" page. The "https" on the iGoogle page that some users visited may have caused these users to believe that any activity performed on their page was protected by https, when in fact only gadgets that are built to support https provide the corresponding encryption protection to users. We made this change to clarify that only activity using gadgets that support https is transmitted over a secured https connection on iGoogle.
For example if you're using Google's official iGoogle gadget for our free email service, Gmail, you can continue to use it with https protection unless you have turned off the default setting on your Gmail settings page.
Valid excuse, but what would be nice (I know it is more work) would be to give gadget developers a way to create https enabled apps. If they are enabled, they work on the secure iGoogle, if not, Google explains why they are not working on the secure iGoogle.
Forum discussion at Google Web Search Help.