I've got OS X Lion installed with XCode 4.1 and there don't seem to be any issues for Starlink. The snow leopard 64-bit binary in http://ftp.jach.hawaii.edu/starlink/nightly/ (I made one at the start of the week before upgrading) works fine on Lion. I have not tested whether a Starlink built on Lion runs on Snow Leopard.

One wrinkle is that Java is no longer installed by default. Running up topcat caused Software Update to run up and this was installed:

java version "1.6.0_26"
Java(TM) SE Runtime Environment (build 1.6.0_26-b03-383-11A511)
Java HotSpot(TM) 64-Bit Server VM (build 20.1-b02-383, mixed mode)

The Java Preferences tool does still exist but it only includes a 32-bit variant of the above Java version. Since Lion is ONLY for 64-bit computers there is no longer any reason to try to work in 32-bit mode for compatibility reasons.

-- 
Tim Jenness
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