Still there as of 13w04a
Yup you're indeed right. I still don't see it as a duplicate of MC-108 though, as it is the update that is the problem here, not the BUD itself (the redstone shouldn't update the piston to go along with the recent change of the fence gates, redstone lamps and such). Also not a duplicate of MC-1263 because in it the issue is the redstone powering the piston, not just updating (it oculd update just fine without powering the piston).
I apologies for the rudeness in the previous post.
It's not this. Did you even read the post ? The block should create a BUD, but does not in the condition said. I would never have listed the issue if it was what you said, i know BUDs enough for this.
It's quite frustrating to get an issue tagged as resolved for duplicate when reading it shows it's something different.
(Edit) Sorry if i sound aggressive.
(Edit2) Or maybe it is ? Does the redstone above the piston acts as the fence gates / redstone lamps did when working ? If it is i still think it should be fixed, but admit the duplicate.
I confirm. It makes any compact sorting system impossible as there is no priority that can be used to sort items. If this is intentionnal to prevent item sorting it's a very bad move, as making something random or even unpredictable is very confusing and prevent any automatic use of it (which is what was very much the point of the hoppers, at least what the community wanted them for).
It looks like the bug happens at the piston level, it may be because of the <1 tick pulse it receive.
http://imgur.com/T8bYBYz