Ubuntu vs Debian

Ubuntu is derived form Debian. But Ubuntu project is moving faster than Debian. Most of the packages get updated and tested with Ubuntu and then they are backported to Debian. Most of the packages which reach Debian test are now, being tested with Ubuntu and if they are working then it is ready for Ubuntu, but it may not be ready for Debian yet because it has to pass thru its quality engineering. The momentum of keeping up-to-date by Ubuntu is very attractive to users. In this way, Ubuntu will be a testing before it is added to debian.!