I believe it does make a difference. But to say that you won't lose weight if you do it at any other time is rediculous IMO, especially if you've never done cardio.
I went from 275 to 230 largely from lifting and running, both at night, usually after 8pm. And that was without a particularly good diet. Over the past couple years, since I've learned a lot about diet, I've stayed between 210-220.
I've been doing am cardio for the first time in my life for the past six weeks, and eating cleaner than ever. Have the extra pounds magically dissappeared? No. However, there has been a noticeable change, slowly but surely.