Yep same here. Still can't access their site, I've noticed that a few sites I use daily are down today - related?
When I started using protx about a year ago, downtime seemed to be quite frequent, losing me sales and not giving a particularly good impression to my customers. So I re-wrote my payment side to take the payment info on my own SSL space and debit the card in the background, if the connection to protx fails, I just get notifed and take the payment later on, the customer is none the wiser.
Well - 3 days in and they are still having real problems it appears.
Such a shame - not least for my frustrated customers and my bank account of course - but mostly because I felt Protx have been much better than most in terms of keeping clients informed and prices reasonable. Protx are not a Worldpay in terms of scale, and attacks like this won't help them.