The file and folder upload options are:
- Web browser HTML
- Javascript enhanced HTML (DHTML/Ajax)
- Browser embedded Flash
- AIR aka. Desktop Flash or HTML/Javascript (formerly Macromedia's Apollo Project)
- Browser embedded Java
- Desktop Java
Browser embedded Flash
Features:
- Ability to select multiple items using the standard OS file picker
Examples:
- Flickr:
- SWFUpload:
- Open source (MIT license) Flash / JavaScript library to take advantage of Flash 9 multiple-upload capabilities.
Concerns:
- Opensourc-i-ness: Although many aspects of Flash are open source. Flash is still considered by most to be a proprietary format, owned and controlled by Adobe.
- Accessibility: Adobe has made great improvements to accessibility in Flash 8, but the reality on the ground is that it is still a lot of work to make Flash accessible.
- Abobe's Flash CS3 Accessibility documentation
- Flash 8 Best Practices:Guidelines for Accessibility in Flash (.html, 4 pages, Overview)
- Best Practices for Accessible Flash Design (Aug 2005, .pdf, 32 pages, Detailed)
- Detailed analysis from a developer of his experience with the accessibility features of Flash(from Aug 15, 2007).
- Abobe's Flash CS3 Accessibility documentation
Abobe Air (Desktop HTML-Javascript and/or Flash)
I'm assuming that all the accessibility issues with regular Flash are true in AIR.