Getting Closer to Real Time With Hadoop

I've been playing with Hadoop for the past couple months, and recently have been using it quite extensively. It's an amazing piece of software and I hope to start contributing to it.<p>If anyone wants to talk start-up ideas involving large data-processing, my e-mail is in my profile.

Anyone have real world experience to share with HBase or Hypertable? Or Cassandra, for that matter. None of these projects strike me as "mature" software but I'd love to learn otherwise.

All today I have been obsessing over Map-Reduce on GPUs. Here is a link (<a href="http://graphics.cs.ucdavis.edu/~lefohn/work/dissertation/lefohnPhdDissertation_highRes.pdf" rel="nofollow">http://graphics.cs.ucdavis.edu/~lefohn/work/dissertation/lef...</a>) to get things started. Still not sure if Java is a good front end to openCL. (Would appreciate thoughtful responses.)