>>> Really, it's not difficult to understand that code testing for "linux2"
>>> will stop working when "linux3" gets released.
>>
>> This doesn't matter. People will still complain. And, as there is an
>> obvious work-around, why not make people's lives easier?
> 
> At the cost of some additional confusion, though.

As you can see, the compile-time nature of the current implementation
causes similar confusion (even to experienced users). With the proposed
solution, most people won't even notice that there is an issue, so they
won't be confused. When they migrate to 3.3, they notice the change, and
accept it as a new feature - and they notice the change regardless of
whether they run a 2.x or 3.x kernel.

With the alternative approach (linux3), people may continue to release
buggy applications for years and not even notice during testing as they
use a Python binary compiled on linux2.