MailChimp Integration

It would be great if a developer created a plugin or extended their plugin to allow integration between Virtuemart/Joomla with MailChimp.

This would allow users to Connect MailChimp to Virtuemart/Joomla store access more advanced marketing tools... Such as integrated coupons, automated emails, cart recovery etc...

All the jazz is here - Sell More Stuff with MailChimp: http://eepurl.com/cXy2Bb

My understanding is that currently this can only be done by way of a third-party site, which is very costly.

I have seen that one, but its not a full integration... We mainly want to integrate the coupon feature to our mail outs, so we can send reactivation mailers to customers who haven't purchased since X days and personalized coupons on their birthdays etc...