VCASMO can play video, like many other video-sharing sites, it converts the video to Flash Video first. The video formats support in VCASMO, you can refer to another blog article here. right now, H.264 video, e.g. MP4, 3GP, MOV etc, VCASMO has to convert to FLV first, too.
VCASMO is also using Flash Video, what is difference with other sites? Firstly, converted FLV in VCASMO, the quality is much better, you can compare the same video in YouTube and VCASMO, you will know the difference:
Secondly, VCASMO has file size limit, but no video duration limit, not like YouTube restricts the duration within 10 minutes. It is because VCASMO is a presentation application, normally a presentation has at least 20-45 minutes.
Thirdly, VCASMO is a knowledge sharing platform, any feature to help knowledge circulate, it will try the best to implement. I think that subtitle is a very important feature. Internet can break the geographical septum, but language is still obstruct human communication. Therefore, subtitle is a free feature for alll free account users, any users can add subtitle to others' presentation. Using the concept of Web 2.0, let knowledge more easy to spread out. The above example, you can see the VCASMO version has subtitle on it.
For advance user, he can upload subtitle file (support *.SRT / SSA). Moreover, subtitle editor allow import others' subtitle. For instance, an user contributed a Chinese translation, you can import it, use his work, the timeline cue point, only translate the text to other lanuage. For instance again, if you think one's Chinese translation is not good enough, you can edit it to another your own Chinese version.