Something to take into consideration - using actual numbers. This is taken from a sample of 31 Imperial Guards (red con) mobs in the room where you gate up to the Emp. Bresham and I were dual tanking, but when I compared his tanking results to mine, I had a lot more data because he was on a conference call much of the time.

So what can we gather from this? Please note that I have counted the critical hits by using my logs, not GamParse. The critical hit count is accurate.
- 331 total hits are considered
- 18 hits were crits (5.43%)
But you say, ok that isn't a named and it is multiple fights. Well it shouldn't matter because they are all the same mob, same max and min hit, same everything and nothing is being measured over time. However, I will entertain your thoughts but be aware that smaller samples are always unwise and often skewed - this is just the nature of parsing ... use LARGE samples such as raid mobs. This is why when you weigh something like getting 6 crits with 3 back to backs during a single fight, you aren't taking the entire picture into view.

Hans tanked the entire fight (except for 1 or 2 hits at the beginning due to distance) and Bresh only added DPS support.
- 47 total hits are considered
- 2 hits were crits (4.25% or 2 crits be fight)
Personal thoughts: until I raid and have to try and keep a tank alive with the mob critting, I can't say for sure. However, from my own collected data, I don't feel like this is a problem yet. However, perhaps if people are unsettled with the idea of mobs being harder, perhaps just reducing the crit rate to 0.5% could be done, but then I ask you, what is the purpose? Why not just leave it at 0%?
I know I personally was critting a lot more last night and I love seeing those 14k backstabs and dropping a trash mob in a raid zone to 50% health on an opening strike. I died 3 times last night, sure, but I'm not afraid of challenging mobs and perhaps am unique in the fact that I don't mind dying and wiping. If there is no fear, there really isn't too much fun is there?
I'm haivng fun with the new crit rates.