Interbike is in October.
When the 2003 bikes arrive depends on the bike and the manufacturer. I have gotten some very good deals in August; on the other hand, I have been shut out of getting bikes I wanted because they sold out in my size nationwide in the Spring and there would be no more until the first production run of the next model year.
It's been my experience that the high-volume models based on Taiwanese frames tend to go on clearance first. And of course the leftovers tend to be very small and very large size frames, which could be a real boon to someoneone who needs one. (The downside is that some shops go to extraordinary and sometimes, IMO, unethical lengths to convince buyers that "we can make it fit, no problem").
It's also been my experience that while the savings on clearance bikes can seem significant -- getting a $750 bike for $600 is hard to pass up -- it's even more important to resist "near-fits" when shopping for bargains. If the bike is perfect, the extra $150 you might have spent will ultimately seem trivial. If the bike doesn't fit, and causes discomfort or pain, it won't be ridden, and you won't have saved $150 -- you'll have wasted $600.
Most of the good bike shops I've dealt with are willing to look around their networks for the right bike in the right size. If it's a leftover, you'll still get the clearance price.