The latest IBM Systems Journal has a good overview of the current TSM
product.  See:  http://www.research.ibm.com/journal/sj/422/kaczmarski.pdf
(The first author always gets the credit.  (Roebuck who?))

It's worth going through even if you know the product, as the authors
touch on some technical tidbits, like explaining Object IDs.
Multi-session restore is addressed, explaining some disappointment in
results due to the nature of serially-accessible tapes, which is leading
to developmental changes in collocation.

  Richard Sims, BU