Well I think the word "love" is bandied about a little bit too freely anyway.
I mean its supposed to mean like...really deep sincere affection but rarely do people use it as such.
Hence why a former member of this forum Ashlyn and I use the term "Deeply in like" to describe feelings which aren't quite love.
I think a fair indicator is when you can TELL the person you love them without fear that they'll say "Uh oh. Too much pressure, I'm bailing." Because you KNOW that they love you as much as you do them...