I'll play devil's advocate on this one.

They have been available on the market as an aurum purchase for ever....or did you forget the times in the original fishbowl where these ruled before the enemy team called out 4-5 tanks on a map that didn't need 1. It is about time people didn't have to pay to win.

So, why would someone use these over the other ones, let's see:

Scenario 1, they are facing 2 heavies or a blob of enemies supported by at least 1 logi with a proto type repair tool, no matter what you do it is a loss with regular grenades; even if you somehow manage to throw all three of your regular grenades before being cut down in a hail of bullets, you will most likely see the heavies either tank it outright or just casually lumber away from danger because you didn't have time to cook it.
-The reverse is also true... there are going to be times when you want a grenade that does bounce around a little.

Scenario 2, you are facing a habitually laggy player... maybe just maybe this will let someone kill them more than once.
-Again the reverse is also true.. that laggy player will probably continue to take no damage but can now not even worry about having to cook a grenade to insta kill me.

So it is a wash, I will wait for the sky to land on me before saying it is falling... that way I know I am mostly correct.

I sincerely hope you are joking and not seriously noting that the contact nades is good weapon balancing for CCP. The fact is this game is just becoming more of a joke every time CCP seems to release new items. CQC will now be just nade spams and ppl will complain heavily about it. Scouts are now completely screwed as these will OHK any scout. So now scouts will only be used as snipers because in CQC these nades will make them into a laughing stock......it also makes the heavy into a laughing stock as well. Only the assaults and logis who can tank 1 nade and then have the speed to run away will likely survive this next ordeal.

BTW......I am 100% positive that if CCP gave imperfects duty to balance the weapons we could have the numbers for the different weapons balanced out in a day. Whether CCP applies those numbers correctly that would be a different matter altogether.