I can see that regular web requests are being compressed which is awesome! However WS requests do not seem to be, according to Firebug:
e.g. http://musicbrainz.org/ws/2/release/8e061dc4-790e-4587-ba53-011e7852f88d?inc=release-groups+media+recordings+puids+artist-credits+labels+isrcs+artist-rels+release-rels+url-rels+recording-rels+work-rels+recording-level-rels+work-level-rels is 1.2MB
Firebug gives me the below (no "Content-Encoding gzip")
with request (accepting gzip, deflate)
This is important for the links like above; MB's bandwidth to Singapore appears to be about 30-40kB/s so it would probably improve the speed of that request significantly.