Wednesday, June 17 is a day many iPhone users have been anxiously awaiting for …. a week?

The iPhone 3.0 OS (up from 2.2.1something) will include cut, copy & paste, landscape keyboard, a very necessary upgrade from SMS to MMS (get your pic messaging on), an improved calender and Internet tethering, among the necessary improvements included in the latest OS iteration.

But what time can you actually plug your iPhone into your computer and download 3.0?

Now.

It’s 10 a.m. PT and iTunes is now downloading and installing the 3.0 update to my iPhone as I type.

No one is quite sure.

But sometime between 9 a.m. and 11 a.m. (PT) is the estimated (or educated?) guess. (I just tried at the time of this posting, 9:39 a.m. and nothing new yet).

So keep your iPhone connected to your computer while continuously hitting the “check for update” box in your iTunes for a 3.0 update. Some time today.

Dwight Silverman of the Houston Chronicle has five things to do after installing the update.

More on the new features:

Apple iPhone developers said the iPhone OS 3.0 software, which includes more than 1,000 new application programming interfaces (APIs), opens the door for new and innovative applications. A new push notification software capability, for example, is expected to lead new applications that provide audible or visual notifications to iPhone users.

And:

In order to deal with the fact that the iPhone doesn’t allow background processing, Apple has implemented a push-notification system that enables applications to gain the user’s attention even if the program is closed. For example, an instant messaging program will stay connected to an Apple server that can send notifications to the user if they get a message, even if the program is closed.

The media functions have also been improved, as podcast playback has been improved, and Apple is bringing the “shake-to-shuffle” feature to the iPhone. Customers will also be able to access and buy movies, TV shows, audio books, and music videos over the air from iTunes, although these files aren’t allowed to exceed 10 MB if they’re downloaded over a cellular network.

It can be said that the iPhone OS 3.0 will have a wide release on Wednesday. What exactly is the release time? It is not known yet.

As Apple rolls out iPhone 3.0 tomorrow, iPhone users can download the software from iTunes for free. However, iPod Touch users have to pay a fee of $9.95.

The update includes many functions other phones have had for a while, including multimedia messaging (if supported by your carrier–AT&T won’t offer it until later this summer), voice recording, buying and renting movies and TV shows over the air, full system search, tethering (again, if your carrier allows it), and push notifications.

Apple has also bundled in some extras, like landscape virtual keyboard for certain apps, more extensive parental controls, in-app purchasing, and a feature for MobileMe customers called Find My Phone.

More Ditails

Many of the iPhone’s long-awaited features will finally become reality Wednesday when Apple rolls out iPhone OS 3.0.

Current iPhone owners can download the software from iTunes for free, and iPod Touch users can get it as well, but for a fee of $9.95, just like the last OS update. What time exactly, we don’t know yet. Apple will only say iPhone OS 3.0 will come out sometime Wednesday.

The update includes many functions other phones have had for a while, including multimedia messaging (if supported by your carrier–AT&T won’t offer it until later this summer), voice recording, buying and renting movies and TV shows over the air, full system search, tethering (again, if your carrier allows it), and push notifications.

Apple has also bundled in some extras, like landscape virtual keyboard for certain apps, more extensive parental controls, in-app purchasing, and a feature for MobileMe customers called Find My Phone.

There will also be stereo Bluetooth available, as well as the capability to create applications specifically for interfacing with third-party hardware. That could lead to a boon in the accessories market for the iPhone as well as the iPod Touch, as my CNET colleague Donald Bell has pointed out.

As anticipated as Wednesday’s OS 3.0 launch is, it’s only the second most important product rollout for Apple this week. The new iPhone 3G S is scheduled to hit stores Friday morning. In the meantime, check out our First Take of the new iPhone and our detailed look at OS 3.0.