Welcome to iOS, Verizon iPhone users -- Apple is sending a carrier update your way! We don't know what it does yet but typically carrier update files control carrier-specific features like personal hotspot, tethering, links, network settings, etc.

Have you gotten the Verizon iPhone carrier update yet? Notice any differences?

[via @techjunky79]

The AT&T Carrier Update (v5.5), required to enable MMS on the iPhone is now live and can be installed via iTunes. Just plug in your iPhone and if it doesn't pop up immediately, hit the check for updates button.

Note: You need to be running iPhone 3.1, so if you haven't updated your firmware yet, do that first.

Once loaded, reboot your iPhone and then head on over the Messages app and you should see the new (for the USA!) camera icon on the bottom left.

For more info, see Apple's support article on the matter, and TiPb's iPhone MMS Walkthrough from earlier today!

Then let us know how iPhone MMS on AT&T is working for you!

UPDATED: Comparing the before and after states of carrier.plist, iambored8907 reports in the comments that the update added PNG graphics for AT&T's new MicroCell (Femtocell) service:

AllowPrefixMatching

CarrierName
AT&T MicroCell
DefaultImage
DefaultCARRIERATT M-Cell.png
FullScreenOpaqueImage
FSOCARRIERATT M-Cell.png

ORIGINAL STORY: Apple today is pushing down a "Carrier Update" via iTunes. As usual, explanations are scant to none. Have you gotten it yet? What carrier are you on, and are you noticing any differences?

(Thanks to Earless Puppy for the head's up!)