Wow XML::Smart simply looks cool.
I'm working on a project at work where I need to pass data between a Java applet and a cgi/mod_perl app on the back end. I've been using XML to translate between the two so I didn't have to maintain a one-off parser for a delimited data format. (Yes I know I need to maintain a one off parser for my custom XML format, but I or the next guy can at least visually parse the XML format and figure it out 6 months from now)
I had been using XML::Simple to build my XML because I didn't want to have to figure out how to get XML::LibXML installed into our production system. I'm still new to the job and haven't figure out the hoops to jump through to get new packages pushed into systems that still have perl4 dependancies.
I however just discovered XML::Smart, and wow this looks nifty. It does everything XML::Simple seems to, without the kludgy interface ... but it also has nifty things like the ability to apply a DTD, the ability to extract the XPath for a node, and probably more widgets I haven't seen yet.