A few weeks ago, I upgraded my MacBook Air from Fedora 14 to Fedora 20. Immediately HaChu 0.17 started playing the opening differently against me. The set of moves it chooses from doesn’t appear to have altered significantly, but the order in which it plays them is significantly different.
The difference is most obvious when I take gote. Instead of opening with a Lion move, it opens with P – 5h. Then when I reply with P – 5e, it still doesn’t bring the Lion out. It either plays the other pawn, or more often it moves a Dragon Horse – either straight back, or more often into the centre (as Black, it often moves the Dragon Horse all the way to the edge in the opening – something it never used to do.) . Sometimes it doesn’t move it’s Lion at all.
All-in-all, once I got used to this style, I find it easier to win against it (with either colour).
I suppose one can attribute the difference to changes in gcc and/or glibc. Or maybe GNOME 3 has greater overhead (I’ve never noticed it – BTW I love GNOME 3 – that was the reason for upgrading).