We just launched a completely rewritten video uploader that greatly increases performance and reliability.
You'll also notice that we removed the "Do Not Resize" and "Remove Sound" options. From now, on videos will never be resized by default, and viewers will automatically get the highest-resolution format that is available for their device. If you'd like to remove audio from videos, you can use the clipper.
Please let us know if you run into any issues with the new uploader at email@example.com.
P.S. You can now upload .GIF files! They will promptly be encoded into smooth streaming video :)