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This just in from 9to5mac.com:

iPhone 3.1 to ship next week, offer MMS and more, AT&T hints...
Tue, 09/01/2009 - 05:46 — Jonny Evans71AT&T has hinted a new version of the iPhone OS will ship later this month, iPhone Software 3.1.

The new software is likely to deliver on some of the promises made to AT&T users when iPhone 3.0 shipped, specifically MMS messaging (at last) and the capacity to engage in Bluetooth file transfers.

iPhone 3.1 will also likely offer support for any of those features we’ve been hearing so much rumour and speculation about, such as social networking of iTunes songs played, potentially a subscription-based streaming music service and more.

Sadly I've already got the 3.1 upgrade installed ... and it doesn't include Bluetooth file transfers.

The 3GS already has MMS though
 
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