As long as it is a finished prototype, I believe it's valid; but I will certainly judge it against the merits of a prototype in comparison to a completed game, the effort I expect from a jam of this length and the quality of other entries. I also tend to take into consideration the tool and what would it allow the creator to do and how long before the deadline it was submitted.
To sum it all - I like to recognize effort; if I reward lazy entries, there is no incentive for others to grow.
Hope this doesn't feel too harsh (what can I do - I'm an old fart... "now, get off my lawn, damn kids!")