Does marginal shortness matter to users?
What is the quantity of urls available per size of url?
What is the rate of usage? I’m sure it’s exploding.
Re: above question, how many month/years left before url size gets too long?
At that point, will companies begin recycling?
I suppose an easy way to deal with this is by allowing shortening at the main site but using another domain as the shortener. For example, tinyurl.com can offer shortened links on tinyurl1.com.