I have looked at the state of different messaging backends recently and i ran a little benchmark to see what is the rough comparison of message publishing throughput. Results that i got are quite surprising.
What i wanted to achieve was some sort of reassurance before choosing a messaging bus for my PHP project. PHP is usually a bit special as it's runtime environment is different than java / .net. I wanted to use rabbitmq because of it's routing flexibility and implementation of AMQP. After the simple benchmark i am not convinced any more if that is the best way to go for me right now.
I have played around with CouchDB half year ago and it's performance was just horrible. I have heard a lot of good about mongodb recently so i thought i will have a look at it.
I think that NoSQL can have really good use cases in web. The problem is that you need a really performant and stable system if you want to use it in production. I ran just a few simple tests so its not a real benchmark or anything. It is just a simple test trying to figure out how far behind are nosql solutions (performancewise).
We are looking for some nice solution to store persistently object-like data. Few weeks ago we had a look at Couch DB and performance looked horrible. We did not even bother to make some more realistic tests as initial data was just disqualifying.
We want to store objects with very dynamic schema and be able to index some of the properties. For example we want all objects of type book with title equal to X. We need it to be very fast. And when i mean very fast i mean memcache-kind of fast ;- )