I'm not sure if this has got any worse with the updated style on StackOverflow, but hyperlinks are extremely difficult to spot in an answer: they aren't underlined (which is a standard idiom) and the color of the text is only slightly different to that of normal text.
For an example, see my answer here. I'm really not at all sure that the OP is going to notice the two links I've embedded in the answer. Can we have the same underlining on SO as we have here on meta?
EDIT: Here is a related question about the visibility of links embedded in code