Well I’ll be damned.

Apple released iPhone OS 4.0 Beta 4 earlier today and it wasn’t long before developers found the strongest evidence yet that tethering for US based iPhone customers may very well happen sooner than later.

Tethering, of course, isn’t new to the iPhone OS and was first introduced back when Apple released iPhone OS 3.0 in June of 2009.

Enabling the feature, however, is carrier and phone specific, and though AT&T kept on promising that tethering support would be coming soon, those promises went unfulfilled time and time again. Frustratingly, AT&T currently supports tethering for smartphones aside from the iPhone.

But with the latest iPhone OS screenshot specifically mentioning tethering and AT&T in the same breath, we can only hope that this isn’t one big tease and that a tethering option will finally become a reality for iPhone users here in the US.

With this year’s WWDC scheduled to kick off on June 7, an announcement regarding AT&T tethering support may very well be on the agenda during Steve Jobs’ keynote.