Here is a white paper on Cart Abandon:
http://dl.dropbox.com/u/46316150/cartabandon.pdf
Main Tips
1. personalize with products price and consumers name
2. send 3-5 in a series
3. keep it clean – remove headers and other distractions
4. timing – under 1 hour has the highest open and conversion but after 1 and under 3 has the highest average order value – test to see optimal timing
By Allan Levy| November 20th, 2011