A 5 part blogpost about the performance of a select statement done with ADO.Net using inline sql, and stored procedures (even some dynamic sql) and then nHibernate to get the same results. But this one has an alternate ending.
This means the Primary Key will not contain the actual auto-increment from the database until the DataSet is updated. Therefore, the auto-increment value is relative to the DataSet only. For this reason, I have found it wise to set the AutoIncrementSeed to 0 and the AutoIncrementStep to -1.
"Driven by the goal to enable simple data sharing across disparate data sources, today, at PDC, we are announcing the Open Data Protocol (OData). " (November 2009)