I'm currently using Bravenet.com's service to manage my mailing list, but I was wondering whether there were any other free services that were better.
Feedburner is what I use. But they do not allow importing of lists. So you must have your current folks re-signup with Feedburner.
Try phplist.com , its free , got lots of features but would need a bit of time to set up. You can easily transfer people from you existing list as well.