My two cents...
Writing XSLT which renders as XHTML is easy.
But simply writing JSPs is easy too.
If there is a chance of porting the application, and say changing it so that it will use web services some day instead of a direct connection to a database, then yes, XSLT in that instance may be better to use.
But basically JSP is the way to go since most developers can more readily support it.
Is it easy to integrate these two platforms to create web-database type applications.
I use JDOM and do XSLT transforms over JDOM elements. I have a web service application which can take any sql query and render it as a JDOM element.
Formatting of the data is all XSLT rendering as XHTML.