Ruby on Rails versus Python
Ruby gets more attention than Python simply because Ruby has one clear favourite when it comes to web apps while Python has traditionally had a very splintered approach (Zope, Plone, Django, Pylons, Turbogears). The critical mass of having almost all developers using one system as opposed to a variety of individual ones does a lot for improving documentation, finding and removing bugs, building hype and buzz, and so on.
In actual language terms the two are very similar in all but syntax, and Python is more popular generally. Python's perhaps been hindered by being popular in its own right before web frameworks became a big deal, making it harder for the community to agree to concentrate on any single approach.
I am in the field of data crunching and very soon might make a move to the world of web programming. Although I am fascinated both by Python and Ruby as both of them seem to be having every similar styles when it comes to writing business logic or data crunching logic.
But when I start googling for web development I start inclining towards Ruby on Rails my question is why is the web world obsessed with ruby on rails and active records so much?
There seem to be so many screencasts to learn Ruby on Rails and plethora of good books too 
why is Python not able to pull the crowd  when it comes to creating screencasts or ORM's like active record.