Self language still alive - new release for Linux, Mac
blog.selflanguage.org
blog.selflanguage.org
Also, its an objects all the way down language, so its quite pretty! (in terms of uniformity of semantics/syntax!)
[added edit] I believe that the documents to substantiate this can be found at http://selflanguage.org/documentation/published/ and I suspect that part of the reason for self's comparative advantage is that by having the core language be so uniform, every control/date structure and abstraction immediately benefits from any improvement in the runtime or optimization techniques (as is the case with scheme and to a moderate extent haskell as well).
Ole Agesen's PHD (about the Self type inference) was the best reference I used for my Master's thesis.
Sun put a good amount of work into the self vm which along with strongtalk, got rolled into the java vm.
He has a role-call at the end of what the people involved in the self project went on to do afterwards, and it's staggering: some of the engineers of the original Google architecture, what became Hotspot as you say, Lars Bak (of Chrome V8) as someone else has pointed out... just an amazing list.