The problem I keep running into with Ruby is that it's so Python-like that I run into this uncanny-valley problem with the idioms. This is, however, a failure on my part with respect to Ruby.

There are a bunch of considerations to take into account when deciding what fits best in that web-application-framework-shaped hole: what the team members are most experienced with ($collaborator knows no Python yet, but might know some Ruby; I know very little Ruby and buggerall about Rails, but there are tutorials), what will be the best tool for the job with respect to features, what will be the best tool for the job with respect to maintenance and the Next Jackass Problem, just how badly I want to use this BDD tool, &c.