It looks really, really interesting - the presentation they have here http://riak.basho.com/nyc-nosql/ explains CAP, Amazon's dynamo concepts, Map/Reduce beautifully. Definitely going to try it.
Only thing I am concerned here is that since the data is accessed over HTTP Stack, won't it become the performance bottleneck.
Glad you enjoyed the presentation, and I hope your experimentation goes well.
Re: HTTP Stack: "Performance" is such a slippery word here. If what an application is most sensitive to is the time it takes to fulfill one request, then yes, the HTTP stack may be an important component to keep track of, as it plays a role in defining the lower bound of request fulfillment time.
However, since all HTTP requests are handled in parallel, and since any node can handle any request, applications whose main sensitivity is not latency, but is instead throughput or availability, are less likely to find the HTTP stack to be a performance bottleneck.
There is also the option of doing away with the HTTP stack completely, and speaking Erlang straight to Riak.
Only thing I am concerned here is that since the data is accessed over HTTP Stack, won't it become the performance bottleneck.