Ok so for those of you that don't read patch notes Ascalonian Catacombs got a buff this last patch. Anet made all the bosses on the explorable paths harder. I've run path 1 and 2 a few times now (haven't gotten people to do p3) and they did indeed make things more difficult.
The Spider Queen has been buffed up, she spits more circles out (6 now) and they will take you down very quick even if you are just in 1. Also her little babies are stronger and their poison lasts longer.
The troll and Lt Kholer have both had some work done. Namely the troll may or may not win. Of my 7 runs (3 of which had trolls) Lt K won 2 the troll only 1.
Path 1) The gravelings are stronger and with the agro nerf to stealth protecting the npc is a bit difficult. This part can still be done with a good kiter and fast killing of the mounds, but it is more difficult. I didn't really notice much other changes until the boss and well he is a pain now. It isn't little gravelings that spawn with him now, its stalkers and up with aoe knockdowns. Ran this path 3 times with different people and we came close to killing the boss a number of times (less than 5% hp on him) but we just couldn't finish him off.
Path 2) Again there some minor changes to parts of the path here, but nothing very serious. The big change was on the boss. No longer can you just mindlessly take him down, you must use the traps and the drop weapons that are there. The key now is to use the guns (skill 1 lifts oozes, skill 2 pulls a lifted ooze) to lift and pull with your squadmates oozes to the traps to charge them. Once a trap is full power you lure the boss to it and it will go off allowing you to damage the boss for a period of time or for a certain % of HP (not sure which it is). One important note here is sometimes after the trap is done the boss will return to being unkillable, but will not more or attack anymore. This glitch can sometimes be fixed by hitting the boss with a knockback or a knockdown.
Path 3) Haven't done this one since patch, but someone that has is welcome to address the changes, which I believe were mostly to the bosses.
While I don't like the change to path 1 (I think its much to hard now). I do like the boss fight in path 2 (Even though we whipped 2 times before we figured it out the first time). It makes for a interesting fight and a welcome change to mindless hacking and slashing and once you know how to do it you find its not that difficult but does require some communication in your squad.