I thought I wouldn't live to see thread like this :X I haven't seen those since 1.5.
In my humble opinion assassin in pvp is one of the most effective class to use and with proper build assassin will run from no other class. As mentioned here several times: the part of skill when playing assassin is not to die. Yes, rangers will pick you from afar, but at the same time those are sitting ducks for stealthing assassin.
Soldiers are toughest match for assassin, but you are never matched against impossible odds like Hox vs Assassin ( it is really absurd for hox).
I am now in progress of making pvp video so I will put my money where my mouth is and show in it fights against T4 geared soldiers.
In fact you can see sneak peak here:
http://youtu.be/rRyHExes3eU
Assassin's CC are faster than Dark Templar's so with proper timing you can not even get hit and burn him down.
I will agree on one thing: low pvp level assassins (1-3) in minis are meat for the meat grinder, but as things progress this class really holds it's own.
Other than that I would encourage everyone not to give up on this class. Yes, it is age of soldiers for now, but still assassins bring a lot to the table.