About a month ago, a friend of mine gave me a cutting (around 10" with several leaves) off her golden pothos plant. Since then, I have kept it sitting in water with in view of sunlight. As far as I can tell, it hasn't rooted yet. Recently, one of the leaves yellowed, so I'm starting to worry. Should I have transferred it to soil right away?
It's usual, when rooting in water this way, to have a cutting about 8 inches max, with about 4/5 leaves (having stripped off any lower ones) - rooting in water takes, usually, about 4-6 weeks, and its much easier done in a small clear bottle so you can see when roots are forming and how long they've got so you know when to pot it up. I wouldn't worry about some leaves going yellow, so long as the 4 or 5 at the top are okay, but you should check regularly for roots if you do not have it in a transparent vessel.