I liked this one as well:<p><a href="http://www.slideshare.net/jrosoff/scalable-event-analytics-with-mongodb-ruby-on-rails" rel="nofollow">http://www.slideshare.net/jrosoff/scalable-event-analytics-w...</a>
I'm working on a system which is similar but higher volume.<p>Have you done any benchmarks to test thousands of updates per second?<p>Same, but on the front-end. What is the impact of generating 10 reports per second for 2 hours? Do the writers get behind?<p>You won't have scaling issues in until the front-end hits some threshold of x queries per y updates, with x servers.<p>Good presentation on another application of mongo.
If you like this, you may want to check out HummingBird...(Node + Mongo)<p><a href="http://webpulp.tv/post/757442457/hummingbird-michael-nutt" rel="nofollow">http://webpulp.tv/post/757442457/hummingbird-michael-nutt</a>
Slide 11 and 12 were interesting because they are close to the same solution, but 11 looks more complicated with Voldemort, et. al. in the mix. HBase with Hadoop seems like another good alternative not mentioned.