People are probably familiar with the Four Seasons line of inks from Sailor, which had replaced the previous standard line (Apricot, Epinard, Sky-High, etc). However, I imagine that a lot of the people that were not involved in the hobby pre-2010 might not have known that the Four Seasons were previously a limited edition release, and that there had been eight others colours released alongside what is now the current lineup. Well, rather, what had formerly been the current lineup. There had been a re-issue of the remaining eight sometime towards the beginning of this year, but from what I understood, it was going to be a one-time thing. Last month, Bruno from Cronica Estilograficas (great blog, got me started on my Japanese pocket/long-short pen collecting streak a while back) reported that they were being re-issued. I was initially confused as to whether he had been referring to the limited, one-time thing, or something else entirely, but as it turns out, it was the latter. It seems to be limited to the Japanese market at the moment, but it does appear to be a complete reissue.
I do like that the newly introduced colours add some much needed brightness to what was a fairly dark palette (Nioi-Sumire and Souten aside), but some of the lighter colours have been criticized as being too light for use in writing (Sakura-mori, Yuki-akari, Fuji-musume - in fact, the previous pink in the standard line, Peche, looks pretty much identical to Sakura-mori, and that was probably the least favourite out of the lineup for a lot of folks). I like the lighter colours myself.
I'm not too keen on collecting the whole lineup this time around. A lot of colours overlap strongly with existing inks in my collection. There are two that do not though (at this point in time): Chu-Shu and Rikyu-Cha.
Pictures all thanks to user Lgsoltek and their reviews on FPN.
Waka-Uguisu and Irori were enticing at first, but I will probably have Chiku-Rin coming in shortly to substitute for the former, and I have two 30mL bottles of Wild Strawberry to substitute the latter.
I've heard that Atsu (cool-japan) will probably be able to get these for you if you ask. I might bundle the two in with a Kobe purchase in the future (probably #14 and #34).