1. Notifications

Notifications in iOS today are interruptions more than helpful notifications: a modal dialog pops up to stop whatever you're doing and tell you, for example, that a text message has arrived – and when you tap it to dismiss that modal dialog, it's gone forever.

In iOS 5, however, a new Notifications Center screen will gather missed calls, voicemails, text messages, push notifications from the App Store, and other such alerts. Sliding your finger down from any screen will bring up the Notifications Center, and swiping across a notification will take you to the relevant app.

2. Newsstand

A new addition to the App Store will bring together a raft of available magazines and newspapers to which you can subscribe – "Most of the major publishers of magazines and many newspapers," said Forstall, mentioning National Geographic, Spin, Vanity Fai, The New York Times, Popular Mechanics, Wired, The New Yorker, and others.

The beauty part of Newsstand is that the publications to which you subscribe will – like those subscribed to using Amazon's Kindle – be pushed to your device in the background. A new Newsstand app will contain all issues in a bookshelf graphic, with their most-recent cover displayed.

3. Twitter

Twitter has been honored with deep integration into iOS 5 – so deep that you enter your Twitter username and password into iOS 5's Setting app, and that account info will be shared by any app that has been Twitter-enabled.

Apple has Twitified a number of its iOS apps – Camera and Photos, for example. Take a photo, tap the Share button, choose Tweet, and you'll see a thumbnail and be able to type in your Tweet, complete with a character countdown. You'll also be able to tap to add location info, should you so desire.

You'll also be able to Tweet Safari articles, Forstall said – presumably URLs – as well as videos from YouTube, businesses and locations from Maps, and materials from other Twitter-enabled apps, without needing to go to a Twitter app. You'll also be able to download Twitter-account photos to add to your contact list.

4. Safari

Safari has been given a facelift in iOS 5. The Safari Reader feature in the Mac OS X version of Safari, for example, will be available in the iOS version, and tabbed browsing has been added to the iPad version.

A Reading List feature has also been added – which appears to mimic some of the capabilities of the current iOS app, Instapaper. You'll be able to access your Reading List, uh, list from your other iOS and Mac OS X devices, as well.

5. Reminders

At first blush, the new iOS app Reminders appears to be yet another app to tell you what you're scheduled to do when, but with one interesting twist: you can set reminders to be location-specific.

For example, as Forstall explained, you can set up a "geofence" around a location, and when you leave that area, it can provide a reminder. Think, for example, of telling Reminders that you need to make a phone call when you leave work. Once you've left your office, a reminder can pop up to tell you to make that call.

6. Camera

After somewhat amusingly referring to the iPhone 4 as being "widely regarded as having one of the best cameras on a mobile phone," Forestall introduced some enhancements that might make it arguably at least as convenient as some other phones' cameras.

For example, in iOS 5 you'll no longer have to unlock your iPhone, navigate to the Camera app and launch it before you can take a snap – you'll double-click the Home button, a camera icon will appear on the lock screen, and you'll use the volume-up button to take a photo. As we said above: "What took you so long?"

You'll also be able to lock focus and exposure by keeping your finger on a chosen spot in the preview image. Also, the Photo app has been enhanced with such additions as crop, rotate, red-eye reduction, and one-click image-enhancement capability as in iPhoto.

7. Mail

As with Mac OS X Lion, the iOS Mail app has been given a once-over, adding such long-needed capabilities as bold, italic, and underlining; control over indentation; flagging; the ability to search for text through all your messages, both on your phone and on the server; dragging addresses between fields; and access to a system-wide dictionary that's new in iOS 5.

Another system-wide enhancement that Forstall used Mail to introduce is an optional thumb-typer's keyboard for the iPad, which groups keys on either side of the display for easier access. This split keyboard is also repositionable on screen.

There's also help for enterprise customers, namely added support for S/MIME.

8. PC Free

In iOS 5's "post-PC world", the need to control many of your iOS device's settings have been taken away from your Mac or Windows PC and migrated to the device itself. You'll now be able, for example, to create or delete calendars or mailboxes on you iOS device, and not have to do so on your Mac.

Software updates can also be done on iOS devices – and, thankfully, they'll be delta updates, meaning only the portion of the app that has been updated will need to be sent over the air, thus speeding updates.

"Now, if you want to cut the cord," Forstall said, "you can," referring to the ability to now own an iOS device without own a PC to which to connect it.

9. Game Center

The Game Center app has received some polish, such as adding photos to profiles, comparisons of achievement points among friends, and seeing friends of friends. You'll also be able to see recommended friends, and get game recommendations.

Support for turn-based games has also been added to the core of iOS, so developers don't have to create that functionality themselves anymore.

10. iMessage

A new app and service called iMessage is Apple's effort to slip a knife between the ribs of the aging SMS/MMS, and to add messaging capabilities to the iPad and iPod touch.

iMessage can also provide delivery and read receipts, and – like many IM apps – it adds a notification when the person on the other end begins typing. iMessages can be sent over both 3G and Wi-Fi, and are sent encrypted.

Notifications of iMessage messages, like other push-notification messages, aren't modal, so they appear in a field at the top of the screen and can be accessed when the recipient wants to access them. Photos and videos can also be sent with iMessage transmissions.

In addition to his Top Ten, Forstall also discussed "more than 200 new user features," including AirPlay mirroring to display your iPad 2 screen on you Apple TV–equipped big screen, automatic background Wi-Fi sync to iTunes, and improved multitasking flick-to-switch-apps gestures