With the XML schema you have right now, I hardly see the point of using XML in the first place. For such data a tab separated file format would do nicely. (You don't have to use XML, even if it's all the buzz right now.) Better than a tab separated file, use something like DBD::CSV, DB_File or the likes of it, i.e. a flat file that can be queried using SQL. That way you can migrate to a full fledged database should the need ever arise (this would imply that you just do a query, the data is permanently available in the database and doesn't have to be read each time the CGI script is executed).
From an XML design point of view, I'd prefer something like
<user ip="18.104.22.168" visits="3" time="1043370125"/>
since data should IMHO not go into the tag names, they're only there to structure the data, not to provide other info besides that.
Just my 2 cents, -gjb-