You’ll find the code snippets under your /lists/ tab ==> design signup forms and response emails ==> "integration code" area. While we were at it, we created a special merge tag that you can insert into your email campaigns that shows how many subscribers you have. So you can say stuff like, "Wow, this newsletter has *|LIST:SUBSCRIBERS|* members!" We’ll insert that merge tag with your current list count. There’s actually a PLEH-thora of new merge tags we just launched, which you can find in the new "advanced merge tag reference" described here.
Update: Several more different styles of chiclets have been added: