I really like Ellen, and I'm surprised it isn't more popular. I mean, it has the oh-so-trendy Ell sound, plus the oh-so-trendy lyn/len ending. What more could a trend-happy parent want, right? I like it so much more than Ella, Ellie, Elizabeth, and Eleanor.
I like it as a first name, but the fact that other ell names are so common would probably keep me from using it as a fn. It makes a really nice mn. I liek Christina Ellen a lot.