Ok, lets start with Germany: 10% off accessories when you buy a Nikon DSLR (full pdf available here).
Nikon UK have announced to dealers that there will be rebates of £50 on D5000 and £30 on D3000 from 5 Nov to 10 Jan, 2009 (Jessops has some Nikon D90 bundle deals and £10 off Nikon D5000 lens kit on their website, but I don't think they are part of Nikon's rebates program).
In the US rebates are announced just a short time in advance. For example few days ago, US Nikon dealers received their rebates schedule for Nov 1 through Nov 21 (I am still working on getting the full details on this rebate schedule). The rebates are mainly for Coolpix cameras and entry level DLSRs (D3000/D5000). I was told not to hold my breath for rebates on PRO level DSLR or lenses.
Right now Ritz Online has a $50 "Nikon instant saving" on the D3000 and $20 on some Coolpix models on their front page.