Bastien, does the current git version contain the new LaTeX exporter? I am asking because I just installed via make up2 (as you noticed) after you fixed the export but and <l> <c> <r> are still not respected in LaTeX export on my Mac. html export works as expected.
#+title: Table test ** My Table | Headhead | headhead | headhead | headhead | headhead | headhead | headhead | headhead | |----------+----------+----------+----------+----------+----------+----------+----------| | <l> | <c> | <r> | | <l> | <c> | <r> | | | 1 | 1 | 1 | 1 | aa | aa | aa | aa |