I have 400 existing newsletter subscribers on mail chimp, I am setting up a new wordpress blog and trying to understand what happens to these subscribers, when I integrate wordpress and mailchimp: Will I need 2 subscription forms, and 2 lists one for he blog and one for the newsletter?

1. now existing newsletter subscribers get a newsletter 4 times per yr. will they be signed up to follow the blog (and get a new email when a new post is added fortnightly) or do they have to sign up separately up for this?

2. new subscribers to the blog will get an email when there is a new post added (fortnightly)
if new people sign up to follow the blog will they also be added to the old newsletter list?