The Yahoo! user Interface blog lists ten cool things you can do with the new Yahoo! Photos.

1. Drag And Drop/Selection Model
You can simply click and draw a selection rectangle around the photos you?d like to copy, or alternately select photos like you would on a desktop using the CTRL or Shift keys. Once selected, you can use CTRL-C to copy or simpler yet, just drag the photos to the album on the list at left; confirm the copy, and you?re done!

2. Keyboard Shortcuts
You can use desktop like shortcuts i.e. CTRL+A and CTRL+C

3. Inline Editing

Click and rename photos without reloading the page

4. Upload Tools
the New Yahoo! Photos provides an Easy Upload Tool that comes in two flavors: a Firefox extension (that works on PC and Mac) and an ActiveX control for Internet Explorer on the PC

And more on the Y!UI blog