First of all, I didn't see any ads. Second, it allows free 3rd party hosting (like posting pics here). PB just cut me off, wants $40 a month for that now.
Flickr doesn't have the single click to copy the photo URL and paste in a post. It's a few more steps involved in posting a pic on forums. That's what happened on post #1, it just entered the URL. Have to use the Image icon here for the photo to show.
Flickr loads faster. I'm still in the learning curve on Flickr. I think I may like it better when I learn more about it. I'm not paying $40 a month for something that has been free for years.
Still trying to work that out. So far, here's what I do. Select the photo from photo stream. Click on the arrow bottom right. The one that sorta swooshes to the right. When the box opens up, select BB Code. Pick the size, then copy the URL code. Paste the url directly to the post. In the url, you can delete everything after .jpg.