Highly unlikely. Sony thinks the Vita is still viable, and isn't about to jump into the rats nest that is mobile component allocation.
Sony's R&D hasn't spiked at all, which indicates they're not researching anything really new, and a new Vita would take away from the core focus of its PlayStation 4. The PS4 is the center of Sony's Games and Network Services ecosystem--it supports all of its subscription services--and a Vita would essentially take eyes away from the PS4 while potentially providing more value to certain markets, such as Japan, who love handhelds+mobile.
Last but not least, Sony is focusing on a mobile-centered initiative by releasing new games on the platform. Sony is also releasing a batch of games that combine mobiles + PS4 in an attempt to engage those mobile audiences.