...and with the polls closed the returning officer steps to the podium and announces...!
(Sorry, that was one for the UK contingent!

)
Okay, here's what (in line with the votes cast above) I intend to do:
The winner of the theme poll for May is "Macro". This will run for May and June (in order to get us lined up on the quarters) and close on June 30th.
During May I'll talk to Sean and work out the best and easiest way of creating / maintaining / linking / hosting an APUG Challenge page which will (hopefully) hold basic summary information of the nature of the Challenge, a description of the current theme and the closing date, history information of past Challenges and anything else that seems like a good idea at the time.
Each quarter, about a month before the start of the new Challenge, I'll start a thread to suggest themes and a week later start a poll to select a theme. Hopefully with the frequency reduced to four times a year, people will find this easier to cope with. (If it doesn't work out in a couple of quarters then I'll try the Neal's suggestion of a once a year voting session.)
I'm going to hold off on the "placeholder" graphic idea for a bit, as in the past some people have posted really excellent submissions either early or late and I think it would be a shame to discourage them. The whole point of the Challenge is to get us out and shooting and trying new things. Being too rigid with the rules probably isn't in our best interests. (However, I haven't forgotten it and it may very well get resurrected at a later date.)
Very many thanks for all the input!
All the best,
Frank