I am not sure the following is exactly what you had in mind, but here goes.
Good examples of successful but (I think) no longer held workshops are Cornell 5 day workshops in digitization and digital preservation. Those were a great blend of theory and practice and the digitization tutorial online is still useful (I actually use it all the time to discuss digitization techniques and standards combined with my own institutions best practices) though old.
Rare book school still teaches beginning TEI but their advanced TEI was a really great class. I also heard great things about their EAD classes.
Archivists seem to have an easier time: SAA has a lot of classes on EAD, Archivist's toolkit and now a whole Digital Archives Specialization. I'll just say I looked at some training from LITA and i was interested: like this class: http://www.ala.org/onlinelearning/management/classes/lita/webservices
I have took one very focused class from Amigos a few years that was very good, an online though synchronous class. It was a good way to try out the technology. Lyrasis is the other big provider of classes, some of which are online.
If you are a cataloger, there's a lot of training at different times of the year. They have their own training culture which I am not that familiar with. They all seem to be learning RDA, whether through classes, webinars, etc.
I think the bottom line is these programs are expensive and unless its something like RBS or SAA and you have a mission to educate, libraries don't have the capacity to keep these going for very long. I think most librarians I know who "keep up" try lots of different things including classes at community colleges, workshops wherever they can find it (if they have funding) and keeping up with Code4lib and listservs. There are webinars through NISO and ASIST too.
I don't know what advice to give you, Trevor because I think its a big question. I'd start with your own institution and see what training would be useful there. I did the training that was useful for me: I think that is the important thing. You won't be useful to everyone so you might as well make the people at MD happy!