I've seen a lot of talk about Oracle adapters for BizTalk 2010.
Is it possible to have BizTalk 2010 without a SQL Server install, or is it too tightly coupled ?
BizTalk only works with SQL server to host it's databases. Check out the requirements.
http://www.microsoft.com/biztalk/en/us/system-requirements.aspx
The Oracle adapters are for integrating to Oracle databases or the "Oracle eBusiness Suite". Whatever that is. I haven't got a clue... :-)