Although you could just calculate dps (damage per second) by yourself, it would be easier if the stat is there for you when you want to buy, especially at early levels. dps and velocity is what most people (probably) look at when they buy weapons (well at least me).

DPS is variable, since the first shot is "free" in a dps calculation, it makes certain weapons less attractive in numbers than they really are.

http://www.myklittle.co.uk/stuff/vendetta/licences.pdf

some stuff doesnt have dps per se, but this list gives a reasonable comparison.

It is just a guide for what players might want, mostly for botting, so it doesn't have to be exact. And if players like heavy hitting weapons better, even if they result in lower dps, than they can chose that.
Also it should only be added to energy weapons, because dps for other weapon types are just useless.

If they do add a DPS field it should have the following text next to it ;)

.... The calculation of such is left as an exercise to the reader.

I thought it just might make the game more "player friendly"...
I'd also take delays being displayed in fraction (preferably over a constant number) of seconds rather than decimal...