The performance evaluation vs Hadoop looks bogus to me. S3, SQS and SimpleDB run on real (non-virtualized) hardware. You need a lot more Hadoop nodes to make it comparable. At least throughput per AWS dollar should be reported.<p>The ~100k files inverted index test is completely unfair to Hadoop: launching 100k map task per small file is ridiculous as it's basically measuring JVM startup time. People/crawlers typically put all these pages in large map/sequence files. Hadoop would automatically launch a map task per chunk (default 128MB).<p>Fetching data to EC2 for computation is also a step backward. It cannot scale on large data as the cluster will become switch bound much ealier than the "kosher" map-reduce, where data locality is observed.<p>In any case, it's neither fast or lean (it's basically Java glue code to use S3/SQS/SimpleDB, and seems to have larger overall carbon footprint than Hadoop)