Some other liquid other than H2O will need to be used, it will need to be hermetically sealed (read tamperproof) and be able to perform for at least 40,000 hours MTBF. No processor cooling system today can function that long without requiring regular maintenance. It will be a challenge developing the specific fluid for such cooling, but if technology can do it, it might just make 100+ core processors a reality.
The real potential I see for this technology will lie in computer graphics/imaging. Think of 100+ core GPU power on a single card? It will make games like Crysis today look like Pacman.