No. Nintendo will just counter a price drop with another price drop, and the 3DS still has 3DS Lite 3DS XL etc to boost sales. 3DS has many good years to come.
Sony is going to beat it in graphics and that's it.
Plus Sony doesn't have the Pokemanz. Don't say Monster Hunter because It's already out on the 3DS (amirite?)
Edit: Also noted you said Call of Duty. It was on the DS and none gave a rats behind. I fail to see how the Vita version will change things. Not to mention Call of Duty is brotacular social game on consoles, have yet to see it work on the go.
It's just that simple.