The calendar's theme is famous historical people, so everyone represents someone from Japanese history. The featured characters are Ichigo (calendar cover), Rukia, Byakuya, Toushirou, Urahara, Orihime, and Renji.
As you can see, this calendar is GORGEOUS. Everyone looks beautiful. You can pre-order the calendar on www.amazon.co.jp, www.cdjapan.co.jp, www.yesasia.com, and other online stores. It comes out on October 27, 2010.
The following is a list of best guesses as to who the characters represent, from 2ch and melodymix:
Ichigo: Sakamoto Ryoma
Rukia: Princess Kazunomiya Chikako
Byakuya: Minamoto Yoshitsune
Toshirou: Okita Souji
Renji: Miyamoto Musashi
Orihime: Murasaki Shikibu
Urahara: Yagyuu Juubei Mitsuyoshi
From Japanese blogger Poppy Moon regarding Rukia:
"Gosakuramachi-Tennou [an empress of Japan] is not famous in Japanese history. chrysanthemum is symbol of Emperor, so I guess Rukia is Kaz[u]nomi[y]a."
"[Ka]zunomiya was very small princess. her high was about 143cm. it's near Rukia."
When she was asked about whether Rukia could be an oiran (like the Clear Soul Plate 2 card), Poppy Moon said no because of Rukia's outfit and flowers.
From nacchan_touya regarding Rukia and Ichigo from the IchiRuki FC:
"I'm pretty sure that she's not an Oiran this time but a Princess/Empress since they put chrysanthemum flowers with her which is Japanese Emperor's symbol and her hairstyle is that of an Imperial member have. KU and 2ch guessed that she is the Princess Kazunomiya, the daughter of Emperor Ninko and Half sister of emperor Komei. As for Ichigo they deduced that he's Sakamoto Ryouma, a Tosanin swordsman and the leader of Meiji restoration.
It would be awesome if that guesses proven to be true because both of those role fits them really well. Ichigo and Ryouma has a similar characteristics, both are outspoken swordsman, had his own principal and both are bridges between two different companies (Ryouma's were Chosu and Satsuma, Ichigo's were Soul Society and Human world). Rukia and Kazunomiya are both noble, have a similar relationship with her half brother (Byakuya and Emperor Komei) and both loves arts very much. Sketchy found a link about Kazunomiya's diary and reading these she does sounds like Rukia XD : here
and just for a fun muse, both of Ichigo's and Rukia's historical characters came from the same era : the Bakumatsu period
Sakamoto Ryouma is known for his role in leading the Meiji restoration, a movement to restore Japanese government from shogun's hand back to the emperor's hand, he worked together with Emperor Komei to overthrow the Tokugawa shogunate. Kazunomiya is Emperor Komei's half sister, she was married to Tokugawa Iemochi as a political maneuver in hope to close the gap between the shogun and the emperor yet that failed because in the end the shogunate era were terminated and replaced back by Imperial rule, at that time the ruling shogun was Tokugawa Yoshinobu, Iemochi's brother.
In short Sakamoto Ryouma teamed up with Kazunomiya's half brother to bring down Kazunomiya's brother in law's reign"
Murasaki Shikibu is known for writing The Tale of the Genji, the earliest novel in human history. The flowers in Orihime's pictures are Bletilla striata, or Chinese ground orchids, which are nicknamed "Murasaki Shikibu." They're usually purple (and "Murasaki" means "violet"). So, that's the reason for thinking she's Murasaki. Murasaki was also a minor noble who served as a lady-in-waiting to various empresses, which probably explains Orihime's simple outfit.
There's a legend that Yagyuu Juubei Mitsuyoshi had only one eye, so Urahara's eyepatch is the giveaway. :D
The rest you can google. Nii-sama's pretty obvious though when you see pictures of Minamoto Yoshitsune.