Summer Usenix conference vs. LISA conference

[Andrew Draskoy]

What is the difference between the LISA conferences and the Usenix
summer&winter conferences?  I used to attend usenixes regularly, but
haven't been to one for a few years.  Anyone care to speculate on which
would be more valuable to someone who's been doing systems work on
UNIX for ten years?  Which one(s) do the other long-time UNIX veterans
go to?  Please reply directly to me unless you think your reply is of
general interest.

Andrew Draskoy
andrew at bransle.ucs.mun.ca