Among these artists are Naru Nanao (character designer of Sola, D.C. Da Capo, and the original Ef: a fairy tale of the two. visual novel) and Puyo (artist of The Melancholy of Suzumiya Haruhi-chan), who have apparently created color inserts for the volume.
Other artists include: Makoto Kubota (Sunred), Motoki Takeuchi (Sister Ruka wa Inoranaide!!), Kumichi Yoshizuki (Someday's Dreamers), and plenty of others...although I can't find a more complete list, alas. That said, it sounds like it could be fun to see all these different creators' takes on the franchise, so I'm hoping we get to see a copy stateside (aheh-ahem, Yen Press?).