When I edit images I do all kinds of subtle color and value tweaks, so my Camera Roll has dozens and dozens and dozens of s l i g h t l y different versions of the same image. The only way to accurately compare and judge the differences is by a/b'ing them...with those arrows. Swiping is utterly useless for that. I have tried--repeatedly--and just can't fathom why Apple's removal of the arrows somehow constitutes an improvement/streamlining/savings.
I use two apps as workarounds, but both have their shortcomings: Yi Zhu's "Ultimate (Photo) Albums" has the bleeding arrows (woo-hoo!), yet takes awhile updating new additions to the Camera Roll since you have to return to the main menu, and any screen grabs taken within it (to, say, compare non-adjacent images) require a re-start of the app. Linkus' "Photo Manager Pro" sports the arrows and full EXIF data...but requires manual image importing. Of course, neither app can delete photos due to Apple's iOS strictures.
So...all that hassle, for what? I have no idea. Apple's ease of use and simplicity policy is all fine and dandy--until it becomes needless dumbing-down. Maybe Apple never heard that a whole new genre was created based on their product: iPhoneography. :|
Link: mashable.com article: "15+ Improvements iOS 5 Brings to Your iPhone 4 Camera"