tedster - 5:16 pm on Nov 25, 2008 (gmt 0)
Thanks for the link, y0z2a. I'd say this is the most relevant quote from that page:
On-Demand Indexing uses a special index that is designed just for Custom Search. The main Google search indexing process is separate and uses different selection criteria, so submitting pages for On-Demand Indexing will not make them appear any faster in the main Google index, or impact ranking on Google.com.