I think I would enjoy something like this. A few tips:
1. Don't spend a long time talking about what you're reviewing or something maybe slightly relevant without doing anything other than talking. Yes, I know that a review is talking about the product, but during this talking I want to see something other than, say, a keyboard sitting there on a desk or just the reviewer talking.
2. Demonstrate the product if possible. The primary reason I watch video reviews is to see something in action. If the reviewer is just going to talk about a keyboard and not actually type on it, how is the video better than reading a text review? IMO, it's not.
3. Try not to make a 20+ minute video, unless you can find some way to make the whole thing interesting/entertaining.
Hope this helps!
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