When I switched web hosting providers, I migrated my wordpress instance by exporting to wordpress XML format (as opposed to doing a SQL export).
I didn’t want the SPAM comments to be imported into the new wordpress instance, so I used vim multi-line search and replace to delete the unwanted comments from the XML.
:%s#
I gleaned that syntax from from [http://osdir.com/ml/editors.vim/2002-06/msg00468.html](http://osdir.com/ml/editors.vim/2002-06/msg00468.html)