I haven't seen them yet, but I believe they are worth it.
I am working on it now. And I get my iPhone on the 18th, so I'll be getting the extra's there. (HARLEYS ARKHAM OUTFIT <3 <3 <3 )
I have a weird obsession with collecting titles and emblems...or in this case backgrounds, icons, and portrait. Modern Warfare 2 was the last game I tried to collect ALL of them, and the only thing I learned was to just try to collect as many as you can. I will at least be trying tho =)