Yesterday, Yahoo! announced the addition of some new features to the beta version of its mail app, which originally debuted earlier this year. Many of these new features are Firefox-centric. Improvements include:

• Integrated calendar at bottom of window
  
• File uploads/attachments take place in the background
• Addition of 'spam' column in message list, and return of 'size' column
• Firefox enhancements: faster composing, smoother scrolling, contact editing, no more overlapping search results (looks like they figured out how to clear floats!)

Having attachments upload in the background is, in my opinion, the best new feature. File uploads take place in a separate, small pop-up window. However, it's not perfect yet. Here's one thing that bugged me: the pop-up isn't resizable, so when I attached a file, the 'Cancel' button was pushed offscreen while the file upload took place:
Once the file was attached, all was back to normal; but that wouldn't do me much good if I wanted to cancel the upload! (If you see this, Yahoo!, that should be an easy correction!)

Overall, I'm pleased with the improvements in this new release, but I'm still holding out for even more. I know, I know... beta testers are perpetually unsated.

What are your impressions of Yahoo! Mail Beta? Feel free to share them here.

(Thanks, Gregg!)

Update: Reader Ryan Kennedy informs us that the screenshots I posted are not from the newest release. Apparently the server farm my account's on hasn't been upgraded yet. Thanks for the correction, Ryan!