BooksOnBoard did NOT take Mobipocket PX orders and money after some time Saturday. Can't speak to the other retailers with certainty because I only followed this story on BooksOnBoard after a certain point this weekend.
BooksOnBoard shut down the ability for customers to buy Mobipocket PX ebooks from its site Saturday afternoon, probably only a short time after the server problem became apparent. The only Mobipocket format you could buy were the Mobipocket OD titles which you could, in fact, download because they come from a different server not controlled by Amazon's group.
BooksOnBoard just reinstated the ability to purchase Mobipocket PX (the affected source) some time this morning. So, Stxopher, at least one retailer puts customer satisfaction ahead of a quick buck. I would bet other retailers did the same as BooksOnBoard, however. I just didn't shop them this weekend because I started looking for OD titles which I could only find at BooksOnBoard.
Their support just wrote that they also now have a dedicated
Mobipocket ebook store as well. Apparently, they've had it for a while. Good to know.