At today’s iPhone 4.0 software unveiling, a slate of new Apple products and usage data were presented in true Steve Jobs style. Nothing was revealed about the event beforehand except that it was for iPhone 4.0 and of course the rumors about iAd.

To be clear, iPhone 4.0 is the newest version of the operating system, not new hardware. It is available for developers now and will be available for iPhone users in the summer. If history is any indication, this will be coupled with new iPhone hardware released at June’s WWDC.

The new 4.0 software includes 1,500 new APIs for developers and 100 new user features. These include the ability for users to create song playlists, 5x digital zoom, gift apps, geotagging photos, homescreen wallpaper, bluetooth keyboard support and spell checker.

But the biggest and baddest feature upgrades were paraded as 7 “tentpoles.”

1. Multitasking: The most awaited and speculated new feature. Many apps can run at once “in the background” and toggled by a new dock feature at the bottom. Finding a way to do this while preserving battery life was why it took so long to roll this out. “Now we weren’t the first to this party, but we’re gonna be the best. Just like cut and paste,” quipped Jobs. (More later on this.)

2. Folders: With an exploding library of apps, it only makes sense that there is now a way to organize them. Users can drag and drop apps on top of each other to create folders. These can be named (i.e., “games”) or the name will default to app predefined categories. The result: the 180 “slots” on the home screen for apps, now fit 2,160 apps.

3. Enhanced mail: The native mail app gets a big upgrade with a unified inbox. This means your inbox can show messages from different accounts (work, personal, etc.). You can now also organize messages by thread so messages with the same subject are collapsed in Gmail fashion. This is logical for an inbox that has only so many spaces and takes lots of scrolling on a small screen.

4. iBooks: Not the most exciting of today’s announcements but kind of neat. This will allow for continuity between iPhone and iPad use: Accounts will reside in the cloud and can be accessed and synced from both devices, including bookmarks.

5. Enterprise: Firmware upgrade that enables better data security, mobile device management and VPN functions for collaboration.

6. Game center: Another logical move. With 50,000 games for the iPhone, this is a central function that lets users participate in social gaming, tracking achievements, leaderboards, matchmaking and inviting friends. Essentially it’s Xbox Live for the iPhone.

7. iAd: Highly speculated and anticipated mobile advertising platform for the iPhone (and soon iPad). This is very cool and will be looked back on as a large inflection point in mobile advertising. This will be the subject of hundreds of more posts in the coming years, the first of which will follow shortly.