I have only heard about mailchimp any other you will like to recommend?
a bolt cutter and a big bucket of superglue to cut off the spammer's computers from the internet and then glue the door to his room shut with him inside.
I was with Aweber, but I have switched to MailChimp recently. MailChimp is better, in my opinion.
Anybody can explain for me more details about Mailchimp?
I use constantcontact (constantcontact.com) to send out a monthly newsletter, paid version.
It is double opt-in; subscribers sign up, are sent an email to confirm their subscription, and then are subscribed. That way, people can't just add a bunch of emails addresses to a database and then start sending out mass emails.
The other one that comes to mind quickly is IMN (imninc.com).
I came across several others a while ago, but they presently slip my mind. A search should turn up many,