I first waited for all episodes to come out - I didn't want to be forced to wait. And before watching "Monogatari Series: Second Season", I did a rewatch of all previous shows, in order they came out: "Bakemonogatari", "Nisemonogatari", "Nekomonogatari (Kuro)". First, it was a good thing I did it, because I really did miss two episodes in first season, because they were released as specials. And second, it really put me in the mood for fresh season.
The new season, "Monogatari Series: Second Season" consist of five arcs. Surprisingly, all these arcs deal with previous girls, while I expected introduction of new characters. But don't take me wrong - this is a superb show and there is no feel of recycling old themes. It's hard to write a one-paragraph blurb since all arcs are very different, but if you liked old seasons (especially if you like original "Bakemonogatari") you will love this one!
First arc came as a surprise. First, there is no Araragi - he is absent and is only mentioned. This means that we see story first time from other people's eyes and it give us a different perspective, especially on Senjougahara and Hanekawa. And Senjougahara is very funny here.
I was again reminded how this show greatly uses nonlinear storytelling. We see (or they are mentioned) a bunch of new characters and previous events that we know nothing about, but everybody talks about them as they were shown. And later when they really are displayed, they came out completely different that we expected. Like constant mentions of first meeting between Araragi and Shinobi (which should be shown in announced movie "Kizumonogatari"). Also, a lots of stories remain unresolved (I hope they are saving it for later). This first arc uses another dirty trick by those missing Black Hanekawa scenes - you will know what I am talking about, believe me.
Another trait of this season is that it the show lost much of it cuteness and became more morbid, serious and violent. It always did have these elements, but they were not so evident mixed with playfulness and fanservice. This is so evident that even the faces changed - Tsukihi is much more rugged than in "Nisemonogatari".