I am using WordPress 3.1.2 and WP e-Commerce Version 3.8.4 and PayPal Payments Standard 2.0. I have a store of electronic/digital goods (sheet music in PDF format).
WP e-Commerce is supposed to be able to work with Paypal, enabling Paypal to submit accept payment and then notify WP e-Commerce of the purchase by changing the status to Accepted Payment. The buyer would then receive a Transaction Results page with a link to download their electronic goods. They would also receive an email with the same links.
But this doesn't work, at least it doesn't work with this version of WP e-Commerce. Instead, I have to manually return to the website to change the status of an order to Accepted Payment. The user, of course, doesn't like this delay as they were expecting to download the product right away.
I've documented my settings and opened a thread on their forum.
I'm hopeful that the developers will be able to reproduce and fix this bug in a release. In the meantime, I've had to close my online store.