Recently updated our server to 1.0.6, wanted to find an abyssal chasm so we made the map. 10 minutes later the map still hasn't loaded, whereas the /locate biome finds it only about 3000 blocks away. Back in 1.0.5 the maps loaded just fine, as we had visited a toxic caves the other day using the map.

Steps to recreate:
On a server, load a biome map and wait as it doesn't load.

Same