Flickr is a popular photo and video sharing service. By using Flickr, you can backup photos & videos to cloud storage and share them with other people in the world. In March 2013, The Verge reported that Flickr had a total of 87 million registered members & people uploaded more than 3.5 million new images daily. You can upload videos up to 1GB for each video. If you are having trouble with video upload, then try to re-save your video as a different video format which is supported by Flickr. Following are the video file extentions that are supported by Flickr: .AVI, .WMV, .MOV, .MPEG, .3gp, .M2TS, .OGG and .OGV.
You can install PicBackMan's Flickr uploader for Mac from the website and start backing up photos and videos.