I'd pick the Lumia 900. Frankly I don't think I'd need that 16mp camera, 8mp would do fine for me in the point and shoot situations. Plus as you said, the Lumia 900 is aesthetically much better. Moreover the Titan II would be too big for me.
If you're on top of the dung heap you're still on the dung. Only difference is you crawled all the way up.