Does weapon power become pointless?

[Shir]

Currently I run around with my trustly Varista! Fear me! With bonuses from my mag, and 2 Orge/Power, my attack power is high 800's. I still have over 30 levels to go before I hit 100, I can only assume my attack power will increase more. Some of the stronger sword type weapons give me an attack in the 900's. With Shifta I hit 999. But wait, this post does have a point!
Lets say I have my Varista with Shifta on, my attack at 999. Do I do the same damage than if I equipped the Holy Gun of Blowing Holes in People (tm)? Since it seems like, before long, any strong weapon will have me at 999 attack, will all weapons be about the same (not counting beast affility and how many times you hit with them).
Is 999 attack = 999 attack, or does it just stop counting there, but stronger weapons can still do more damage?

[Azarath]

stronger weapons still do more...or so it would seem i know what you mean about the shifta i use it all the time and every thing has a 999 atp but some thing hit for more even though the % is the same

[Spy]

ATP power goes past 999, it just doesn't show anything above it.