Today is the official launch date when the Mango update will go public to a limited number of customers, presumably those with carrier-unlocked devices. The general delivery timeline for other users, bound to a specific carrier will be extended till the end of October. The "Where is my phone update" page is the central tracking point for this kind of information.

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Windows Phone OS 7.5 officially supports Internet Connection Sharing (ICS) with up to five devices being able to connect to the created wireless network. However, this capability will be tied to what the carriers decide to offer, limiting its usage by non-carrier based devices.

Mango introduces such new capabilities, like:

• multitasking
• more integrated apps
• primo mobile web browsing
• powerful personalization tools (integrated social networking and conversation threads)

Mango devices already went on sale in Japan in Russia, and more are coming up in North America later this year, like the HTC Radar 4G.

More details available here.