Reading the *.fmw with FME (using a TEXT READER) and counting for instance TRANSFORMER occurences or something? Nothing within the FME environment AFAIK.
Hi Johann - Interestingly I was convinced that in Windows tootips you'd get back exactly what you are looking for. I knew I had seen and used it before but in Windows7 the tooltip doesn't show, so perhaps it's a setting in the OS somewhere. However, I have a WinXP VM and just as I had remembered, you just hover your cursor over the file and...

Thanks ! It worked.
With WinXP, the number of transformer is displayed in tooltip : 1540 transformers !
I had the same result editing the fmw file, counting occurences of "XFORMER_NAME".
Yes, long ago we did a shell extension for Windows XP that showed a bunch of metadata about a workspace. I think you could see the information in the windows explorer table view by exposing more columns as well.
Sadly, the interfaces we used went away with WIndows 7. I realize this is useful so we'll look at bringing it back.
Or maybe we should just make a .fmw READER for FME that would tell us things like this :-)