Read about the new PICAXE stuff here
Just last week I was kicking myself because I wired a circuit using the one pin on the 08M that could do infrout to a plain old LED instead of a IR-LED. Now it doesn't matter just order a 08M2 and drop it into the 8 pin socket and I am good to go. Nice!
18m2 was there for some time before the whole new line came out and I must say that I had a very satisfying experience with it!