I like that it is easy to upload my own pictures as well as those of other photographers or people in general! It's also good for sharing with friends who don't have flickr accounts themselves but would be interested nonetheless.
The only thing i dislike about this app/site is how slow loading time can sometimes get if you're uploading many images at once (as opposed to just 1). This isn't really an issue though since there are alternative apps out there which do allow multiple image uploads without slowing down your computer too much. If anyone wants quality photographs uploaded quickly then they should use FlickR instead of any others because it does what its meant to do very efficiently!