Apple Shipping Refurb iMacs »

Jordan Golson at MacRumors:

New iMac models on the Apple Online Store list a lead time of several weeks to get delivered, while the refurbished models claim to ship in 1–3 days, with $200 and $230 discounts on the low- and high-end 21" models respectively.

If you need an iMac now, this is the way to go.