I always thought that stored procedures were there to move data logic from the applications to the data store. So that you could take advantage of the same logic (bugs and/or fixes) in all applications that dealt with that data. So, when you have a Java application, a .NET application, a perl CGI script, etc., all accessing the same data, providing various views (and/or methods of access), they can use the stored procedures to do common work, whatever that may be.

True, they somewhat tie you to a particular vendor. But the same can be said about tie-in from .NET or Java, or that evil Larry Wall. And, if you write your stored procedures in, say, Java, you may not be as tied in as you may think - most of the logic will be moveable, only the actual APIs would be different (and not always all of those).

I suppose it depends on precisely what you're putting in stored procedures...

Anyway, back to the original question - is your application living on the same machine as the server? If so, stored procedures won't offer as much benefit - part of their appeal is that they can deal with large quantities of data with much less network overhead.