Historically the trading period has occurred after the rule proposals were in and voted on. So as you make trades for 2007 remember that rule changes have not been proposed yet. Some proposals may impact your trading needs if submitted and approved.
I agree with Ken. No trades should be official until any rule changes have been voted on. But I leave it to the discretion of the benvolent and merciful YOC.
I'm not going to halt the trading season, mostly because pretending that it hasn't already started is futile.
But everyone should be very midful of the point that Ken is making - all trades completed prior to the voting on rule proposals is subject to the results of those proposals. In other words, buyer beware until the rule voting is done.