In my opinion this is a space which is still open for companies to grab.. a difficult nut to crack, but still open for grabs.
Grade A colleges - Don't need placement help (at-least that's what is portrayed to outside world), but they still need assistance.
Grade B colleges - Not much focus on getting students placed
Rest - No idea
Products offering placement services may not be good idea, but products offering assistance in providing a network for colleges to pitch to companies is good.
Agree with Anisha that LinkedIn was better placed to solve this than others.