Cisco recently addresses defect/feature request CSCus14734 by adding "http-status-code-ignore" to the IP SLA HTTP operation.
Since IP SLA HTTP only supports HTTP and the vast majority of web sites immediately redirect to HTTPS with a 30X status code, the IP SLA operation fails with a "not 200 OK" response.
If there was an option to add http-status-code-ignore to the HTTP operation, we could use it to test reachability and web service for a lot of commercial services.
Thanks - Al