I think it does, although not precisely as described in the SO post above: in SPDY the request headers are compressed separately before any TLS compression woul

I think it does, although not precisely as described in the SO post above: in SPDY the request headers are compressed separately before any TLS compression would apply, so the attacker would have to put her guess of the cookie in the request headers or the URL (as the URL is sent as a pseudo-header in SPDY).