Apple touted the service's ability to recognize when you're messaging someone else eligible for iMessages, but it appears to be limited to e-mail addresses at this point in the BETA. Delivery confirmation is turned on by default, but those of you who don't like the thrill of the chase will be happy to learn that there's an option to disable read receipts.

ENGADGET: Apple iOS 5 hands-on preview

The Seattle, Washington-based company is asking developers to submit an e-mail address to be notified when a "limited beta" of the Kindle Development Kit starts next month.

FORBES: Stopping Apple: Can Amazon Find An App For That?