There is no built in option of listing which licenses are in use, however I have attached a SolidWorks Enterprise report generator file that will display current licenses in use.
ShowUsedPDMWELogins.crp.zip 627 bytes
by using report generaton we can know which type of license used by which user and on which machine
below is more for monitoring flexlm licenses, I am guessing that you PDMWE might license directly from the database, but you may want to find out similar information for your solidworks license usage as well.
yep, I agree nothing built in but there are actually a ton of choices, but a bit hard to find. I have written a paper on this but it didn't make it very far. I am not sure if postings on the old forum made it through but I have posted much of this information before.
There is a huge variety and complexity and costs...
SAMReport Lite - is hard to find, typically shipped with autocad products (at least link and recommendation) and I have never bothered to set it up.
phplicensewatcher - this is the one I use, a bit hard to setup, but free and great options after you are done
cacti with flexlm addins - again free, and one I use, but harder to setup
openlm - paid for I think, so haven't tried it but probably one of the best out there.
x-formation - I reviewed and looked good but never pursued.
do a google seach for 'flexlm license monitor' and you will find a host of information.
http://nerhood.wordpress.com/2006/09/25/managing-your-flexlm-licenses-with-cacti-and-phplicensewatcher/ -- a quick post about the two tools I use.
Here, since september, we use JTB FlexReporrt. So far it does the job. In addition of total number of licenses used, I can keep statistics on who used what and for how long.