Why? oh! Why?you may ask.
It depends on how you use that new blood.
A very good way to use the new blood is Season of KDE. You get new developers, features that interest them and some mentor to help them if they find themselves lost. Almost sure a win situation. This way we are getting a person (Rafael RodrÃguez) to try to fix the VERY SLOW rendering of patterns in okular.
Then there is the bad way, and sorry Jonathan, i know i kinda promised you not to bitch more about Rosetta, but i have to. That nice Translate This Application button is the worst executed idea ever. It redirects you to a page where people will translate applications for KUbuntu (potentially overriding real KDE translation) and people will not know they are not contributing to KDE, moreover this people probably won't know the style used for translations, so their translation will be totally out of the rest of translations.
The good implementation of that idea should have been putting that person in contact with the KDE translators team, but that would remove the KUbuntu coolness from the equation ...