YouTube - Is it good for uploading professional videos?

YouTube after taken over by google has emerged as one of the most popular video hosting website.
But the question is - Is it really good for uploading professional videos?

Here are few facts to help us understand more about these video hosting websites.
The user-made video hosting concept started in late 90's . Today there are more than 20(maybe even more) free video hosting websites. Out of which YouTube has its own share of popularity.

Because of this reason, I decided to upload few videos on YouTube . I think it is one of the simplest and easiest site where one can upload a video. But YouTube seems to degrade the quality of a video.
One of the main differences in YouTube and other sites is the freedom of selecting a thumbnail image. It might seem to be a simple thing, but is very crucial in case of uploading some professional videos. Following are few things which one should note when uploading a video on YouTube -
1) YouTube doesnt take the initial image for thumbnail of the video.
2) It provides you with 3 choices (approx. the image after the video is played for 25%, the image after the video is played for 50% and then third image when it is played for 75%)
for eg. if your video is of length 1 min. The three thumbnails you get would be approx. image at 15th sec, 30th sec and 45th sec.

This forces us to have the most important part of our video to be at exactly at the center of the video. I see this as a drawback and definitely a thing to be considered while using YouTube to upload professional videos.

As compared to others, Vimeo gives choice of 9 thumbnail images and so on.