Now that they are at relatively similar price, it's really down to 2 factors.
_ are you interested in blue ray?
(I personnaly ain't, but if you are, count this as being worth about 2-3 exclusives)
_ how many exclusives of each interest you?
Halo 3, Halo3 ODST, Halo Reach, Gears 1, Gears 2, Fable 2, Fable 3, L4D, L4D2, Forza3, LO, shadow complex, GTA4 addon, Alan Wake
FFXIIIvs, GoW3, MSG4, Uncharted, Uncharted 2, GT5, Valkyria Chronicles
Then if you believe the popular rant on this site (new IPs or refreshed (KZ)): Killzone 2, LBP, WKC, Demonsoul, Haze, Heavy Rain
(sorry i'm not big at folowing unreleased exclusives but they have 5 and 6 respectively there...)
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