This is very very very cool, If i recall my pl research lore correctly, self even ~ 15 years ago had runtime/compiler tech that was at least par with 10 year old java.
Also, its an objects all the way down language, so its quite pretty! (in terms of uniformity of semantics/syntax!)
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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).
David Unger gave a great talk recently on this: http://www.youtube.com/watch?v=3ka4KY7TMTU
(recorded at Stanford, but it's a reprise of his acceptance speech on receiving the Dahl-Nygaard award from memory)
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.
The team responsible for the JIT in Self went on to develop HotSpot (see http://en.wikipedia.org/wiki/HotSpot#History). Probably just to prove the point, someone wrote a Smalltalk implementation in Self which outperformed the commercial Smalltalks available at the time (I don't have the details to hand, but there's a video talking about Self available on YouTube where it's mentioned).
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).