In my previous post, I mused about how the changes to POS standings may change the nature of POS warfare in highsec. In brief, I believe that POS will become more desirable (both in looting content and utility), but that at the same time POS will be easier to move and there should be more free slots.
But there is a change I failed to mention, one that has happened already.
There are several ways to defend a POS. Of course, the most desirable is a large fleet to crush your foe... but that's not always available. However, a POS is not easy to destroy and its innate defences can be improved . One is to have so many hardeners on that the POS has so much effective HP it's just not worth the time to blow up. Another is the "death star"method, where your POS is bristling with firepower (something that works best with a gunner manning the guns, the gun AI isn't very clever). The last one though is the "dickstar" method - have your POS field so much ECM that it's just impossible to establish a lock on it. (see here)
The "pure" dickstar method doesn't work anymore in highsec, as it has a new counter: the Marauder. In bastion mode, marauders are immune to ewar... so all that ECM will be gleefully ignored as the marauder fleet pound your POS to scrap metal.
However, marauders aren't necessarily the be all end all of pos-bashing ships, as they themselves have a counter. When a marauder goes in bastion mode, it stops moving. POS can field capital ship guns*. These guns are useless vs moving target, but can track an immobile marauder no problem... which tends to hurt if you have enough guns.
This doesn't mean that ECM can't be a part of your POS defence strategy. But you can no longer rely uniquely on it, as it can easily be countered.
*POS gun sizes are weird. Unless this changed very recently, small POS guns are medium sized, medium guns are large sized, and large guns are capital sized... and capital sized guns won't be able to track subcaps at all, making them quite inefficient in high sec... but having a few at hands to shoot at marauders might be a good idea. Remember you just have to anchor them, you don't have to turn all of them on at once.