The implementations are different.
As usual, Apple takes something that exists and improves it. They've implemented fingerprint scanning for purchases in place of putting in a password. Hopefully in future they'll let you login to apps and websites by scanning your print (by storing passwords that are accessed by scanning your print; not by sharing your print with websites/apps). Also, all you have to do is place your finger on the scanner and it opens up and unlocks on the 5s. With the Atrix you still had to hit the power button to turn the screen on and then scan.
I haven't read about whether TouchID works in the dark or not, but the Atrix scanner doesn't. Would be interested to know this, if anyone has read any information about it.
It's also multiple years later, so I would hope the technology has gotten better.