The first thing I purchased after I bought my DSLR/kit lens combo was the 50 f1.8, and I enjoyed it so much, I almost stopped using my kit lens completely after that. The IQ difference, and ability to adjust aperture down to 1.8 is a great advantage.
Whatever you do, I would leave yourself some $$$ to get the 50mm f1.8.
I also have the f1.4, and it is definitely better built, but you can learn and do so much more with the f1.8 over your kit lens. I also liked having a smaller/lighter lens on my DSLR when I was going out shooting. I would put the kit lens in my shoulder bag and walk around with the DSLR/50mm around my neck. The 50mm is a great focal lenghth, yes it will limit you at times, but that is why I carried the kit lens in my bag, just in case I was somewhere that I needed to go real wide or zoom in. Otherwise, I shot almost everything with my 50, and the IQ difference is pretty big.
Also, just to mentioned, you said you are interested in the 60d as you plan to hold onto it for 5 years, but that model is 2 years old, and the t4i is the latest rebel model. I haven't researched this, but I think the t4i might have better ISO performance, and while many other features are great to have, that is a big one to consider and research. I do know that the t4i has the newest digic processor, while the 60d has the previous generation of processor. Just something to think about. If I plan to keep a piece of technology for 5 years, I prefer to have the most recent iteration of said technology, for that reason, I'd look strongly at the t4i. Especially if its cheaper, and even more so if the ISO performance is stronger, as I suspect it might be.