This update addresses issues that, in extremely rare cases, could result in data loss when upgrading a library from an earlier version of iPhoto.

Data loss, eh? Sounds terrifying. On the surface, it is. A brief search through the Apple Support forum reveals users who, at first blush, apparently “lost” their entire iPhoto libraries after upgrading to version ’11 (which is actually version 9.0 of the product).

The most commonly reported problem is a frozen upgrade process. After installation, the first time a user launches iPhoto ’11, they must upgrade their existing library if they want to use it in iPhoto ’11. Sadly, for some users, the upgrade never completes. Instead, it never gets past a spinning progress indicator.

The problem isn’t all that common, nor is it irreparable, though for those affected, the fix is quite convoluted. Some have apparently even had to restore from Time Machine backups.

For the record, I haven’t had any problems myself, despite upgrading multiple libraries ranging in size from a few hundred megabytes to a 300GB. I have found that iPhoto slows down considerably as it churns through the Faces database.

Another reported problem with iPhoto 11 is missing help files. Once again – I couldn’t reproduce the problem on any of my Macs. But if you are having problems accessing Help in iPhoto 11, you can find a solution here.

iLife ’11 was, for me, something of a mixed bag. I expected more from Apple, and the few updates we got to some of the iLife titles didn’t set my world on fire. Even though I haven’t experienced any problems myself, seeing library upgrade problems like these cropping up only makes me even less enthusiastic about the suite.

Let us know if you’ve had problems with iPhoto 11… or whether you intend to upgrade at all.

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Slideshows have been enhanced with some new themes, including a new holiday theme. However, more impressive than holiday cards flying around on ribbons in front of a snowflake background: the new email feature where you can send sets of pictures with HTML templates directly from within iPhoto. It’s another feature that seems borrowed from the iPad.

The real benefit of including the email templates inside iPhoto is that you can rearrange the photos, resize them, and edit to your heart’s content before sending the message. Facebook and Flickr sharing have been updated as well, and iPhoto will automatically download pictures to your iPhoto library that have been added to these online services.

Printing books and cards has been improved. Books now use better application logic to decide how to lay out pictures, using the key photo from the iPhoto album for the cover and grouping together pictures that were taken at the same time and in the same place. iPhoto ’11 will also recognize the star ratings you’ve assigned to your photos, and will give preference to higher-rated pictures for the bigger spreads.

Letterpress cards are a new choice that use embossed paper to add a high-end custom-made feel to your printed cards. There’s even a video demonstration of how letterpress cards are made to explain this option to iPhoto users.

iPhoto ’11 looks like a solid upgrade with several enhancements that will make sharing photos by email, Facebook and Flickr easier, improve slideshows, and make printed books and cards even better. I think the full-screen interface looks interesting but I’ll wait to pass judgment until I’ve had a chance to use it. It’s clear that Apple is moving towards full-screen all around and is even featuring this approach in the next version of Mac OS X (10.7). Perhaps iPhoto ’11 will be the canary in the coal mine to show if this approach is a great innovation for the desktop or a simple gimmick designed to ride the coattails of the iPad.

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