Thanks, after the first shock the difficulty has been adapted automatically and there are practically no new dead shares. So that part is fine.

Here are 3 images - first from cgminer console, second from p2pool console and third of cointerra web console. The first two seem to be more in agreement now - I guess they all have different time window, so in average they must agree (though web console shows consistently the lowest value). However the numbers are not encouraging.

http://s10.postimg.org/fomcg5ssp/hashrates.png