Application to store/browse/view photos?

"Picasa for Linux should have these functions

Check this link for a feature list:

Sync your Picasa 3 and Picasa Web Albums edits

Tired of having to manually re-upload your photos after making further edits? By enabling 'Sync to Web,' edits made to your photos in Picasa 3 are automatically transferred to your corresponding online albums.

Retouch your images

Always want to be airbrushed? Use the Retouch tool to remove unsightly blemishes and improve photo quality. It can also help you to restore old photos with marks, water stains, and scratches to excellent condition.

Add text or watermarks to your photos

You can easily personalize your photos using the Watermark and Text tools.

Print captions

Your captions are about to see a little more action. You can now print your captions or photo file names on or below your photos.

Upload easily to Picasa Web Albums

Use the Drop Box to hold quick uploads and upload throttling to multi-task during your upload.

Control your Picasa Web Albums settings

If you have an online album in Picasa Web Albums, you can now control the online settings through the corresponding folder or album in Picasa 3.

Manage folders on your computer

It's now possible to move entire folders around on your hard drive from within Picasa 3.

Get more information about your photos

We've added new icons and tools to the Library view to quickly communicate useful information about your photos.

Edit: changed the link!"

"It sounds like the software you were using was associating tags with images in its own files, instead of using IPTC Keywords, which are embedded in the image file itself.

So you'll want to look into software that does exactly that: tag images in the file's metadata. This way, if you ever move your files, the tag will stick.

On WinXP, the two applications I use for organizing photos do this job pretty well: Photoshop Elements 6 and ACDSee. There's a couple more examples there.

Bonus: If you ever want to upload your images to a smart website (i.e Flickr), the tags will automatically be imported."