According to Bessatsu Margarette March issue, Shiina Karuho's Shoujo manga "Kimi ni Todoke" was announced to get a TV anime adaptation. It will be aired from this autumn.

The publication of the manga Kimi ni Todoke in this issue was canceled due to the author's maternity leave.

Source: Scan of the cover of Bessatsu Margarette
Source: Scan of Bessatsu Margarette 2
Source: Comic Natalie

Updated
According to Bessatsu Margarette July issue, the production staff of "Kimi ni Todoke" anime is as follows:

Director: Kaburaki Hiro ("Zenryoku Usagi")
Series Organizer: Konbaru Tomoko ("Nodame Cantabile", "NANA")
Character Designer: Shibata Yuka ("Makasete Iruka!")
Production Studio: Production I.G

Key illustration of Kimi ni Todoke Anime

Sources:
Natalie
Production I.G.

Updated
Cast
Kuronuma Sawako: Noto Mamiko
Kazehaya Shouta: Namikawa Daisuke
Yano Ayane: Sawashiro Miyuki
Kurumizawa Ume: Hirano Aya
Sanada Ryuu: Nakamura Yuuichi
Yoshida Chizuru: Sanpei Yuko

Sources:
Scan of B Margarette
Scan2