Due to the release of the Title System a "new" set of wings has been released on 20th April.
The new chests cost 800 HanCoin (HanCoin = Wc-Wp) and, besides the new colors and names, their movement speed is different as well (I'm not sure if all wings are alike).

Lv 1 wings: 10% movement speed
Lv 2 wings: 11% movement speed
Lv 3 wings: 12% movement speed
Lv 4 wings: 13% movement speed
Lv 5 wings: 14% movement speed
Lv 6 wings: 17% movement speed

The new wings - with their Japanese and English names - are the following

New Wing Chest

Souzoushi Wings (Creator's Wings)

Seirei Wings (Spirit Wings)

Hiryuu Wings (Wyvern Wings)

Hikari Wings (Light's Wings)

Phoenix Wings

Datenshi Wings (Fallen Angel Wings)

Akuma Wings (Demon Wings)