Perhaps they are still selling Allegro on unix systems too, hard to know but having two code bases can be a real challenge to keep up with and keep the interfaces the same.
Now ranting aside for a moment, I think it is really good for PCB design. When you look at things like the shape editor and compare that to what other vendors have in their tools Allegro is a clear winner. The UI is also very fast. They have the power under the hood but accessing that power just needs to be refined.
In todays market place with many PCB cad vendors the lack of library managment in Allegro has to be a very hard sell, in-particular when you compare what cadence is doing to say the likes of Altium or Mentor. They are very very weak in this regard which translates to "Less Sales" in the long run, and a PITA for the end users of the software.
Another area they are weak in is with what I call Nested commands. Suppose you are routing a trace in and you want to change the grid size, well you can do that with a macro or the UI but if you do your current operation of routing will be lost so you have to go back to the routing Icon. This might not seem so bad but in the real world little things like this add up, I can site many examples. Click, click, click gets Old really fast. It is like trying to drag that horse to water, Not an easy task.
The Killer though is the Out of the box setup time required to be somewhat productive with the tool. Out of the box, with allegro for a first time user or seasoned PCB designer = Zero Productivity. If you do manage to keep your hair in-place and figure out the wierdness of the way the tool works then it can be very good.. But again that hump at the start is more like a mountain just to get productive. Couple that with the lack of good PCB Footprint creation and library managment "WTH is a symbol anyway" They are called "Footprints" in PCB Editors ! someone send cadence a memo on this : )
Means more sales for other PCB vendors and a shrinking user base for cadence with their PCB software.
Wonder if Library Managment is on the list for a re-hash in V17 ?