I personally use ProStockMaster for just key-wording...not all the other bells and whistles it comes with. A lot of people use different programs and some prefer one over the other, but ProStockMaster is free.

  I didn't know you could attach any metadata to a video file. How exactly do you do this? My understanding was that you have to send a separate file for this.

Whoops I misunderstood...I thought the OP was talking about photos. I don't do video so I have no idea.

  I suppose it's possible to attach keywords to a video file, but i'm not aware of any website that has that enabled. I don't do it that way. I just create a text file on my computer and copy and paste the keywords, title etc. If you want to upload a separate file, at pond 5 I think you upload a .csv file . At istock, i think it's a text file. I tried it and it's not any faster for me because I'm only uploading 5 or 6 files at a time. Read the FAQs at the sites for more details, or ask the forums at the sites.