I went to Library History Seminar XI last week with some other folks from SISLT . It was ok, as with most conferences the presentations were all over the map, some were interesting, some were not. You would think that since LHS is only held every 5 years more people would present their best research, alas this was not the case.
Some words of warning, Robert Allerton Park and Conference Center, where LHS was held, is in the middle of nowhere. Be prepared for a drive to Urbana-Champaign for any food, bookstores, or alcohol. ( The library conference triumvirate) Connectivity is spotty at best, very few computers, phones, or TVs. Cell phone reception is also hit or miss.