There's a reason "J" is worth 10 points in Word feud, it's a quite uncommon letter.
According to Lewand, arranged from most to least common in appearance, the letters are: etaoinshrdlcumwfgypbvkjxqz Lewand's ordering differs slightly from others, such as Cornell University Math Explorer's Project, which produced a table after measuring 40,000 words.
Here's a graph measuring the frequency of "J" in words: https://en.wikipedia.org/wiki/File:English_letter_frequency_(alphabetic).svg
Here's a graph measuring the frequency of "J" in names: http://home.uchicago.edu/~jsfalk/misc/baby_names/images/initial_all.png
Sure, there's a lot of words with a "J" in them (not many relatively), but there's very few words starting with "J". Yet, there's an abundance of names starting with "J". Here, I'll list as many as I can from the top of my head.
Name starting with a J: Jack, Jackie, Jackson, Jill, Janet, Jeremy, Jeremiah, Jake, Jesus, Jacob, Jock, John, Johnny, Jon, Joe, Joel, Janus, Jerry etc.
Words starting with a J: Jar, Jigsaw, Job, Jacked, Jest, Jester, Jeopardize, Jeopardy, Jaguar, Jitters, Jumbo, Jet, and probably some more.
Now, is there a reason for this. Heck, is there even a great difference between the number of names starting with a "J" and words starting with a "J"?