ATOM feeds have been enabled. (RSS is not supported, but most readers should read both.)
When adding a feed using the base directory "forum", you'll get two options, a general forum feed and "new topics". The general forum feed doesn't seem to work.
New Topics - First post of each new topic
flashcardsdeluxe.com/forum/feed.php?mode=topics
Comments, Questions and Feedback
flashcardsdeluxe.com/forum/feed.php?f=2
FAQ
flashcardsdeluxe.com/forum/feed.php?f=3
Developer's Blog
flashcardsdeluxe.com/forum/feed.php?f=4