I think school plays a huge part. While JD is more "mature" in a sense than other forums, a lot of the members here and elsewhere sort of fit that category of 13-25 which covers high school through college.
For me personally it's the busiest time of the year and I'm out in the field 3-4 days a week. No students to help out and all the work still has to go ahead, so not only do I have the paper pushing, but also the field work. Not that it's a bad thing.
September malaise is pretty common for North America at least. BAck to school is pretty deeply ingrained and for those of us in Canada and the northern US, summer is essentially over, regardless of the weather. I'm contemplating depressing things like putting away the golf clubs, lawn mower, etc. Not real happy thoughts.
I'd be surprised if the distribution is having an effect. I've been busy and not able to keep up on threads, but lots of stuff is available. I say it all the time, but if you guys really want to see poor distribution, come to Canada, it'll bring tears to your eyes. 3-packs, clone wars items, lots of people finding stuff. If not, just a lull before Christmas stocking takes over the shelves and toy aisles blossom in size.
Collecting waxes and wanes for sure, with everybody, but usually not synchronously. Maybe too much product for a change? EU was only about 8 or so figures, clone wars is going to be how many?
A mix is probably right.