OK, I guess it's time I too hop on the AOP bandwagon. Basically, I know nothing about AOP save a few of Rickard's ramblings I've read and a couple web pages I read back when AspectJ was being heavily promoted (I hear AspectJ is dead now, is that right? A professor of mine worked on AspectJ when he was at Xerox Parc, maybe I should talk to him about all this AOP magic).
Petri Net Reading. The Application of Petri Nets to Workflow Management - van der Aalst (ResearchIndex) is probably what I'd call the starting-point in your journey through CiteSeer to accumulate knowledge of Petri nets. Brett Morgan had asked that I produce references to the papers I read to go from zero to Petri in 2 days. Overall, W.M.P. van der Aalst seems to be the shinig light in the world of Petri nets for workflow systems. For what it's worth, petridish supports coloured petrinets, but werkflow does not take advantage of them. Werkflow has exactly one colour of token flowing through the network:... [bob mcwhirter]
Man, I really should go read up on this stuff when I get a chance, though I'm sure most of it will be well over my head :)