Higurashi no Naku Koro ni Kai Review
Bizarre Luminescent Jelly 2: Schoolgirls from space...
I'll assume that if you have any interest in this anime, you've already watched the first season already. If you haven't go do so right away (and do check out the excellent official anime review of it on The Escapist first). Kai will make almost as little sense to you without watching the first one as the watching the first one without watching Kai afterwards does.
I won't write much on this, at it is supposed to be a mystery after all, but the overall tone and themes differs somewhat from the first season. Where that one focused on the psychological battles the characters had with themselves (the their decent into violent derangement when they usually lost that battle), Kai picks up on the brief theories on the Hinamizawa syndrome touched upon in the first series and runs with and adds considerably too that, making for story which is much more "external" in nature. While I preferred the original approach, a solution to this whole bloody mess, including the annual murders not committed by our group of all-to-flawed heroes naturally must leave the the minds of a closed group for the larger environment to make any sense. It would have been nice to see another season like the first one before Kai though, but there's really nothing wrong with it: it's just very different, and perhaps overall less original than the first one, as it's themes have been seen in anime before. The Horror aspect is also cut almost completely in favour of the Mystery and "traditional approach" ones, so those who loved it mainly for the Horror may be in for a severe disappointment.
While the first series utilized all of its characters in the club well, giving each of them opportunity to shine in the different arcs, after the first arc of Kai, the focus is almost entirely on Rika, Keichii, a new character and to some degree Satoko, while the others never leave a (diminished) supporting role. Rika, the young priestess who occasionally showed glimpses of a far wiser and world-weary side in the first series (and knowledge of the time-skips), is fleshed out considerably, with many a revelation of the true and tragic fate so intertwined with the fate of Hinamizawa. Keichii brings his optimism, energy and cunning to the table, an ever valiant fighter in a battle lost a hundred times before. The new character is an old friend of Rika, but gains a role of its own later on, becoming an important part of the cast. And Satoko pretty much just hangs out with Rika.
Since I loved the different perspective alternating between each character brought to the series, I'd consider this a step down: but on the other hand, and answer arc needs far more continuity and focus (aside from a recap episode, which in defiance of lazy tradition barely reuses any footage from the original, there are only 3 arcs spread across 23 episodes), it's probably hard to avoid.
The visuals have been upgraded to a smoother and slightly more detailed look, although it's not really all that noticeable. If anything, to me it actually makes the screen seem covered in Vaseline sometimes. The Japanese voice actors are all the same (an English cast is (thankfully?) not yet available), and as good as they ever was. Nothing is wrong here, and Higurashi wasn't really about technical achievements in the first place.
While those who have watched and enjoyed the first Higurashi season would hardly be swayed from watching this one (as they're basicly a single unit), I'm happy to report that you'll probably do so with pleasure. While certainly less original than the first one, and losing much of its horror appeal, it still skillfully ties together the plot threads, and is an amusing (if at times draining) watch.
A note on availability:
As this anime is not yet available in the western world by legal means (and you should be wanting to pay for something as good as this), the only way to legally acquire it currently seems to be Malaysian copies with English subtitles (or the original non-subtitled Japanese DVD sets if you can understand it). Whether they've licensed it or the copyright laws there are just lax (copies come with an official holosign of "inspected by the Malaysian government", so they're hardly illegal bootlegs), if something is legal in the place of origin you can freely import it (paying due customs and all), at least in the jurisdiction where I live. You'll just have to pray that you'll eventually receive your copy, that the English subtitles are tolerable, and that the government haven't censored it to shreds, which may vary widely between releases for all I know. Overall, it's probably far safer to just wait for a western release, although when and if such become available is currently unknown.