Sony have confirmed the games that will be joining and leaving PS Plus' instant game collection next on the official PlayStation Blog. You've still got a few days to download/register your "purchase" of DmC, Remember Me on PS3, or Don't Starve and Resogun on PS4 as seven games are leaving and only 5 games are being added. That said, with games like Bioshock Infinite and Metro: Last Light joining there's certainly no reason to complain.
Leaving PS Plus:
29th January: DmC Devil May Cry
29th January: Remember Me
29th January: Soul Sacrifice
29th January: Blazblue Continuum Shift Extend
29th January: GTA Liberty City Stories PSP
5th February: Don't Starve
5th February: RESOGUN
Entering PS Plus:
29th January: Metro Last Light
29th January: BioShock Infinite
29th January: Dynasty Warriors Next
29th January: ModNation Racers: Road Trip
5th February: Outlast