*blush* Thanks, Talli!
Unfortunately, Sanjeev, we haven't implemented the recurring part. We're looking at annual billing, not monthly, so we have some time to decide what to do when the first batch of subscriptions comes due.
As far as selling subscriptions goes, it's mostly pretty straightforward. I ran into a lot of bugs when I first started working with the 4.2 Oracle version of ecommerce but the current ecommerce module has been through several rounds of bug-fixing so it should be all better now.
I didn't set prices to zero, though; they pay for the subscription just like any other product, but shipping is set to zero.
Good luck!
PS Yes, the situation for credit card clearing is pathetic here as well.