>Schemas and namespaces. Is there an online "this is what you really need to know" guide out there?

Though it's XML through MS' eyes, I visit msdn.microsoft.com/xml failrly often. There are good articles on various XML technologies with lots of sample code.

>I have some XMLized cursors that I want to send to MSSQL (as updategrams?)

Mmm... no. UpdateGrams comform to a strict spec (you can find that spec on the MS site as well).

Depending on the format of your XML, you will need a process to parse it out and performs the SQL updates.