A NeoGAF user discovered two new trademark filings from United States Patent and Trademark Office filed by Sony Computer Entertainment America this April. Based on the description of the filings, these are definitely intended for potential video games rather than services.
SCEA filed a trademark for a game called Entwined. Some speculate that it sounds like a game Media Molecule or Quantic Dream would develop. I highly doubt that the latter would be developing this game since we know that they already registered the domain "singularityps4.com" just like how the previous websites of their games even before the PlayStation 4 came out. Secondly, we have a title called KILL STRAIN and it intentionally has it in all caps. It sounds like a zombie themed game or a possible spinoff to the Killzone series, but truthfully we don't know much as of the moment except for what the filings tell us.
We do know that this will be an exclusive since it was registered by SCEA, but if the titles will be developed by a first or second party studio remains to be seen. While people might get excited by more games on the PlayStation 4, these games could be available exclusively or in addition to PlayStation 3 and PlayStation Vita.
For more news on PlayStation, check out our latest post on the new details regarding PlayStation Now before it launches in North America this summer.