Not sure if this will reach anyone (since this is an old thread), but we've made a lot of improvements to http://whomined.com.

For developers --

API:

http://api.whomined.com - return JSON whith last 144 blocks
http://api.whomined.com/#blocknum  - return JSON with 144 blocks from blocknum
http://api.whomined.com/miners - return miners statistic and short info
http://api.whomined.com/miner//  returns last 144 blocks mined by miner staring with