This is problably too late and I'm probably missing something but
given amount of generators/iterators introduced in python 3.X
(http://docs.python.org/release/3.0.1/whatsnew/3.0.html#views-and-iterators-instead-of-lists)
file.readlines() seems a good case where an iterator can be more
appropriate than a list.
I realized it while writing this recipe:
http://code.activestate.com/recipes/577968-log-watcher-tail-f-log/
In this specific case, having readlines() yield a single line at a
time would save a lot of memory.
Maybe we can introduce a new parameter to do this?