I've expressed my distaste for the way holiday bosses used to work before: fighting the same dude (at least) five times in a row just to see the fight? No thanks.
But lo and behold, along comes the dungeon finder for holiday bosses and I've been completely converted. You don't have to do the fight more than once anymore and it doesn't even hurt your chances at one of the rare drops since they go directly into a personalised satchel that's only available once per day anyway. Not to mention that it's extremely fast; even as dps I never had to wait more than five minutes so far. I don't know if that's simply because the fight is short or if there really are a lot more tanks queueing up - the ease and speed of the fight probably encourage a lot of people who usually feel intimidated by the notion of tanking a full heroic and the possible abuse they might expose themselves to in there.
The two frost emblems you get in your satchel are a nice bonus as well. A bit silly really for a whole five minutes of effort, but what the hell - the new expansion is drawing near and soon all our gear will be replaced anyway, why not let people gear up their alts while they still can.
Oh, and speaking of gearing up alts: so much love for the ilevel 232 cloaks for every class and spec. So far, good cloaks have been one of the things that are slightly harder to come by, at least if you're not swimming in frost emblems and thus own one of the frost emblem cloaks. Without raiding,, the best drops you could hope for until now were from the normal ICC five-mans and heroic Trial of the Champion, but they didn't cover everyone's stat needs optimally, and the best the vendors could offer you below frost level were these valor cloaks that haven't excited anyone for one and a half years. Across all my alts I've already acquired three new cloaks from Ahune (including for off-specs and the like) and I'm hoping for another three before the festival is over.
Oh, and until then, any non-useful cloaks that I might win on greed rolls can be vendored! Joy! It's been so long that I visited Ahune before this year that I can't actually remember for sure how his loot in specific was handled before, but I remember other holiday boss loot having no sell price so if nobody could use it, it would just rot there because there was nothing else you could do with it. Hopefully that won't be the case anymore for any of them, as I hate having to leave sparkles behind.
The one thing that threw me a little was how easy the fight seemed compared to what I remember. The last time I fought Ahune before this week was two years ago, when the level cap was at seventy, and I remember him being quite a tough bugger that took a long time to kill. On my recent attempts however I didn't have a single party that didn't down him the first time he withdrew into his frozen core or shortly afterwards. I remember in the past he would easily go through two or three phases at least, and didn't the elite adds spawn much more frequently as well? That said, I'm not complaining - he's clearly not meant to be much more than a holiday loot piñata, and I can live with him being just that.
All in all I really have to give Blizzard kudos for the changes they made to the system here. It's not entirely without downsides (I've seen comments from people who miss being able to boost their lower-level friends and alts for example), but as far as I'm concerned this is one change where the good definitely outweighs the bad, and by far.