I am not quite sure what you mean. Wordpress has a feed generated standard most times it is located at /feed, so no need to have a program to 'generate the xml'. Also on feedburner.google.com you can select the publicize option en activate the email subscriptions. Everything when you have a new post on your wordpress then the next day it will be send to the users that signed up.
As you are looking for a alternative check out mailchimp which gives you a lot more options to choose from. Better stats and also temptation.