This is probably a very hard question to answer, but does anyone have any idea how many man hours it takes to build a program like Amarok, Dolphin, Kmail, etc.

How many man hours in all of KDE?

I just think this would be an interesting thing to know. Obviously it's difficult to quantify exactly, but someone on the inside should have a rough idea or be capable of a guess.

I remember reading an article on the Linux kernel and it said it took some thing like 250 man years to get to where it's at now.

there is this neat tool called sloccount that gives a good estimate when you feed it with the sourcecode. For deeper insight look at http://www.dwheeler.com/sloccount/ . Or, if your's on debian, just "apt-get install sloccount"

https://www.ohloh.net/p/kde

At the bottom of the right sidebar you can find estimates on person years of creation and cost. Ohloh got almost all big projects, so those values might at least be good for comparing, I woulnd't recommend using them for anything but advertisment though