Except that's not really true.
If we look at which console has established more new IPs this gen, MS is the clear winner. Sure, some of those IPs aren't exclusive any more, but the fact remains that they have established and supported more new IPs this gen than Sony.
You also say they keep serving up Halos, Forza and Gears.
Sony have released 3 Uncharted's (four if you include the vita release), 3 motorstorm's (four if you include the vita release), 3 Infamous', 3 Killzone's (four with the upcoming vita release), six God of war titles (4 hd remakes and counting Ascension), 2 LBP (four if you include the vita release and karting, 2 hawks, and I'm sure I'm forgetting some.
MS have released 3 Gears (if you count next years release), 3 forza's (four if count open world release), 2 crackdowns, 2 alan wakes, 5 halo titles (six if you include 4, two of which were a new direction for the series, one was a remake) and...????
Sony is just as reliant on its 'core' title releases as MS. MS have also developed just as many new IPs this gen as Sony as well as supporting new third parties IPs.
You left out quite a few.
Quantic Dream is basically a second party dev at this point- so Heavy Rain was a new IP, as is quantic dream's followup Beyond: Two Souls
Sony owns the IP (and assisted in development of) Demon's Souls
Heavenly Sword isn't remembered much these days, but was a big part of the PS3 launch
The Last of Us hasn't yet released, but will
The Last Guardian hasn't yet released, but will
LocoRoco and Patapon are PSP titles, so hard to quantify whether they count as "this gen" for you
Gravity Rush is an awesome vita title
Sports Champions is one of the only reasons worth owning a move
MAG was an interesting experiment in multiplayer gaming, but not my cup of tea
Unit 13 is a followup by the same studio that created MAG..yet to be released but will soon
and even with that I'm sure I'm forgetting a few things that might be PSN exclusive, as well as first party series that existed during the PS2 era like Gran Turismo, Sly Cooper, and SOCOM.
The quality and sales figures vs microsoft's first and second party efforts might be up for debate, but Sony has easily twice the volume.