That's awesome to hear man. I've been improving as well so I have a pretty good idea how pumped you are. I recently purchased a new seat (Selle SMP Dynamic) and find that I'm now able to stay down in the drops for a much longer period than before. I think this is helping me with my speed. My time on a 10 mile loop (I don't get a lot of time to ride) improved today by just over a minute from last Thursday's ride. I work with a guy that's faster than me and trying to catch him has been my motivation and the improvements I've made have been very fulfilling.
Congrats on your improvement and keep up the good work.