There won't be an event for the xserve and mac pro alone, since when has apple garnered for media attention towards their pro level offerings? Media events always surround consumer products, like the mini and iMac, but it won't happen unless the products are redesigned. The iMac isn't due a redesign, and if they did redesign it would be stupid because then they would have redesigned all their consumer computers in the space of six months, leaving them no redesign events for a couple of years at least. The mini is due a redesign, so could be a possible focus for an event, but the iMac is their best selling desktop by far, so when they do update it, leaving it as an "oh by the way the iMac's getting a spec bump" during a mini-focused event, like they did with the air at the macbook event, does not seem like the right move. The air is a high end product, and the macbook sells far better. No, when the iMac is updated it will be a press release on a tuesday, and the mini would either get its own event, or just be slipped out quietly as well (if it even does get a redesign this time around).
