(Since Nise is the sequel to Bakemonogatari, I would have to say that you definitely need to have watched the first season...or you're really going to wonder why Koyomi puts up with an office supply wielding girlfriend, a yaoi fan/basketball player, board game jailbait, a 'I-only-know-what-I-know' it-all, and a gradeschool pun-master ghost.)
Story (8/10): Even with the focus brought around to Koyomi's little sisters Karen and Tsukihi, they don't always get the focus squarely on them. And truthfully? That's not exactly a bad thing (most of the time). While we get new material (obviously), viewers that watched Bakemonogatari will get to see our lovely ladies and how their stories continue, with the main one being Senjōgahara and her objective of putting her past behind her. The twists that Karen and Tsukihi's story puts us through are entertaining and helps change how we see the oddities that popped up in the first series. Though, I will say that it feels like Tsukihi got the shaft (no pun intended) with her story arc, since it only seemed to remember she existed halfway through.
The biggest strength of the story is the dialogue. Every conversation is important to your understanding of the philosophy of the story and why characters do what they do. While not every conversation will be clear as to it's meaning (and trust me, they won't), they all make up the whole of the story. With the strength being the dialogue, it can shift more easily between comedy, darker themes, romance, slice-of-life, and anything in between.
Art (9/10): This being a Shaft production, Nisemonogatari looks good. All the character models have changed slightly to reflect the passage of time and look just as nice as they did before. I do have to wonder what prompted Shaft to start adding in some more realistic facial designs (since they look a little...off, I would say?), but since this series tends to thrive off of surreal imagery, it tends to fit more often than not. If anything did bother me, it's that it seems like the colors got washed out for the majority of the show and everything just looks a little too pale, and the backgrounds for the show were either weird architecture or blank walls, with no middle ground. But when that's all I have to nitpick, it just shows how much work went into the whole design of the series and how good it came out.
Sound (8/10): All of the songs that appeared in the show are good, with each opening doubling as a character song as well. I liked Karen's and Tsukihi's openings the best, with them just being a lot of fun to listen to (especially Tsukihi's Platinum Disco. Good luck trying to get that out of your head). The ending, Naisho no Hanashi, by ClariS was good, as is all their work, but I will admit that I missed Kimi no Shiranai Monogatari.
Character (9/10): Really, it wouldn't be a Nisio Isin work without the amazing characters from the first show. All of them have matured slightly from our last viewing of them, and I couldn't be happier. They all have strong personalities that make them a huge step up from other harem-esque shows. Koyomi is still his slightly-cynical, pervy, hero self and it just is a lot of fun to watch him take in the events of the story.
While all of the characters are great, I'll have to be completely honest- the entire show was stolen, for me, by the full introduction of Oshino Shinobu. While we only saw her as a mute, underpowered little girl last time, we get the full monty here. And by God is it glorious. She's just so clever and fun to watch that she became my favorite character (her interactions with Koyomi are really fun and interesting, so check them out for sure, since they reveal a lot about how their relationship evolved from the still unreleased Kizumonogatari).
For the character that I didn't like, it would have to go to Nadeko. All we really see of her is in one episode, and it was dedicated to her trying to get in Koyomi's 'good graces', so she didn't come off well. (Granted, I have no idea if it's like that in the book, so I can't be too hard on her in that regard). I'm hoping that she get's a little more development soon, though.
Enjoyment (8/10): From philosophy to fanservice (some welcome, some interesting, some uncomfortable), Nisemonogatari is fun and addicting. You want to see what the characters talk about, what oddity is the main focus of the arc, what more little shout-outs Shaft can cram in. It's just a blast to watch and think about. Plus, you do get some awesome fight scenes (aka Koyomi getting beat to a bloody pulp, but winning the war with words).
Seriously, I love the Monogatari series. It's smart, fun, and intricate, making it a real treat to all the viewers who turn in. I highly recommend it, but I will warn you that if you didn't like the mountains of dialogue that made up Bake, Nise isn't going to change your mind (also if you think the infamous Toothbrush Scene isn't your cup of tea).
