A little list of popular titles that I feel are overrated.

Overrated Rating
X (movie) Awful
Wolf's Rain (OAV) Weak
Voices of a Distant Star (OAV) Decent
Tsubasa: RESERVoir CHRoNiCLE (TV) Good
Toradora! (TV) Very good
Tokko (TV) Good
Texhnolyze (TV) Decent
Star Driver (TV) Not really good
Soul Eater (TV) Very good
(The) Sky Crawlers (movie) Good
Rurouni Kenshin: Reflection (OAV) Awful
(The) Qwaser of Stigmata (TV) So-so
Queen's Blade: The Exiled Virgin (TV) Not really good
Queen's Blade 2: The Evil Eye (TV) So-so
Phantom ~Requiem for the Phantom~ (TV) Good
Penguindrum (TV) Decent
Pandora Hearts (TV) Not really good
Now and Then, Here and There (TV) So-so
Night Raid 1931 (TV) Decent
Neon Genesis Evangelion: The End of Evangelion (movie) Very good
Neon Genesis Evangelion: Death & Rebirth (movie) Decent
Neon Genesis Evangelion (TV) Good
Naruto Shippūden (TV) Decent
Naruto (TV) So-so
Mind Game (movie) Good
Metropolis (movie) Not really good
Memories (movie) Decent
Love Hina (TV) Good
Kite (OAV) Bad
Kiddy Girl-and (TV) Weak
K-ON! (TV) Very good
Jin-Roh - The Wolf Brigade (movie) Bad
He Is My Master (TV) Decent
Gurren Lagann the Movie –Childhood's End- Very good
Gurren Lagann the Movie – The Lights in the Sky Are Stars Very good
Gurren Lagann (TV) Very good
Guin Saga (TV) So-so
Gilgamesh (TV) Not really good
Gantz (TV) Bad
FLCL (OAV) Very good
Final Fantasy: The Spirits Within (US CG movie) Decent
Final Fantasy VII: Advent Children (movie) Decent
Dragon Ball Z (TV) Good
Dragon Ball GT (TV) So-so
A Certain Scientific Railgun (TV) Decent
(The) Book of Bantorra (TV) Decent
Bodacious Space Pirates (TV) Good
Blue Drop (TV) Decent
Bleach (TV) Good
Blassreiter (TV) Good
Black Cat (TV) Good
Black Butler II (TV) Good
Berserk (TV) Good
Basilisk (TV) Good
Bamboo Blade (TV) Good
Arjuna (TV) Not really good
Aria the Animation (TV) Decent
Angel Links (TV) Decent
Android Kikaider - The Animation (TV) Decent
Ah My Buddha (TV) So-so
Agent Aika (OAV) Decent
5 Centimeters per Second (movie) Good