Just in case anyone is looking for the resize feature when uploading, I just uploaded some photos and went looking.  I found the following answer:

Your original files are always stored for all of your uploaded images. The option to resize or change the size of your uploaded images is not currently available on the new site. Images uploaded to the new site are stored at their original sizes. However, we sometimes create smaller copies for display purposes on the web. A web sized (1024X768) copy is created for easy display of large images. Smaller images are displayed at their original size.

We suggest you resize your photos to the resolution you would like to link them as, before uploading them to your account. That way any images that are smaller than 1024x768 will remain that size when linked out across the web.

You can also resize images after they've been uploaded to your account using the editor. Check it out here!

Looks like you need to resize before uploading.