Photos: extant examples of reefs from the Great Barrier Reef that are used as analogs for the ecological structures anticipated under the paper's coral reef scenarios. Photos by O. Hoegh-Guldberg.
A post on Dot Earth, Carbon Dioxide Is Double Threat to Reefs, summarises non-technically.
P.S. 14 Dec: The Guardian reports this as Acidic seas may kill 98% of world's reefs by 2050.