MarketPress, Multisite and SSL

The latest update is fantastic because now I can offer my subsite sellers access to different payment gateways instead of just PayPal chained payments.

Now that I can do this, I need to get a better understanding of SSL. I haven't used it before, but I understand what it is - how does it work with MarketPress?

I've opened up the following gateways to higher level Pro Sites members: Stripe,, MoneyBookers, PayPal Express, and PayPal Payflow. I know that some of these (at Stripe and Authorize) require SSL certificates.

If I install an SSL certificate on my server (I would just pay my hosting provider to set it up for me), how does it work for the subsites, and how does it work with Domain Mapping? What kind issues do I need to be prepared for and anticipate? Is there a tutorial available for using SSL on a multisite with the different gateway variations?