I've had a busy week so haven't been that active on the Arena for a few days, but I do check any PM's if I get them due to the notifications I get through e-mail. It seems these notifications haven't been working properly because I received one today, but upon my check over here I saw I had several more from around the 21th of May?
It does seem to work again, but was it just me or did others have the same experience? The e-mail notifcations aren't in my spam box either.... weird....