iTerm2 does not remember spaces when relaunching.
I have three windows which get restored correctly each time, but all of them gets restored to the current space.
Seen in latest nightly and in the special build 'Build 2.9.20150521'.
Darwin marklar.local 14.3.0 Darwin Kernel Version 14.3.0: Mon Mar 23 11:59:05 PDT 2015; root:xnu-2782.20.48~5/RELEASE_X86_64 x86_64