We at "El Viaje Imposible", my production company, are working on a quite complex short film. I have casually discovered a great tool that we are using to review videos remotely:
1) The artist uploads a video that needs to be reviewd.
2) The supervisor (the "boss") can play it, stop it anywhere, and paint over any frame adding some text.
3) The artist can later click on a comment in a list to access that frame directly and read the information, and then upload a new version of the video on top of the old one, to keep the old comments.
We are using it to fine tune the animatic of the short movie, while in preproduction, and it works great.
"CreationFlow is a web-based collaboration software for digital art production which aims to manage the review workflow between designers, bosses and clients thorugh visual reviews over images, videos and pdf files using a built-in mark-up tool." (edited partly, from their web).
If you are interested in this tool drop me a line and I will let you know about an interesting introductory offer that you can get through us.