I just upgraded to LLBL's 1.0.2005.1 version and my code broke in one place

Dim exp2 As ORMQueryExecutionException = DirectCast(exp, ORMQueryExecutionException)

Dim paramCol As System.Data.IDataParameterCollection = exp2.Parameters

The exp2.Parameters now returns an IList instead of IDataParameterCollection. But what about the items in exp2.Parameters; are they still of type System.Data.IDataParameter

Yes.

This breaking change is in the migrating your code section though.

Sorry that I was not clear in my question. What I want to know is:

an item in exp2.Parameters; is it still of type System.Data.IDataParameter ?

It's the Parameters collection of the query executed. So it can be casted to a SqlParameterCollection and contains the SqlParameter objects, if you're using sqlserver. It's no longer converted to an arraylist, but contains the full parameters. Every parameter implements IDataParameter interface, so I think it will always contain parameters of that type. If not, let me know.