Speed isn't necessarily the primary advantage that MapReduce provides; it's more about shifting the burden of scaling backend process from the programmer to the infrastructure.
That said (caveat: I don't have a lot of real world MapReduce experience), in my line of work, I do a lot of analysis at less than web scale (there's still a lot of business value there too, folks!), and just the thought of writing a bunch of MapReduce jobs just to achieve the analytical capabilities in vanilla SQL alone is not a pleasant one.
If people have experience in getting around this, I'd love to hear about it.
That said (caveat: I don't have a lot of real world MapReduce experience), in my line of work, I do a lot of analysis at less than web scale (there's still a lot of business value there too, folks!), and just the thought of writing a bunch of MapReduce jobs just to achieve the analytical capabilities in vanilla SQL alone is not a pleasant one.
If people have experience in getting around this, I'd love to hear about it.