Why don't more people use LEDs for lighting rooms?
There are all the problems you mentioned, but this is being addressed as the technology improves. There is a big push to bring more/better standards to LED lighting, because right now (Q1 2014) there is little accountability in terms of lighting quality.
While the bases of retrofit LEDs quite happily work with existing fixtures (for example, the regular Edison screw in E26/27 base), often the size of the LED itself does not--especially for recessed fixtures or certain types of track lighting. Many LEDs do not meet ANSI standards. Usually this is because of the heat sink and components required to manufacture a well-performing bulb.
Also, the payback period is often over two or three years for household use and that's not good enough for most people. But, there are many companies that finance lighting upgrades today where you can pay with your electricity savings.
Even if you don't outfit your entire house in LEDs, it makes financial sense to replace the bulbs that are on for the longest number of hours per day, as well as those bulbs in hard to reach areas (save yourself from having to get out the ladder every 1,000 hours like you do with incandescent bulbs!).
