Pretty much this right here, the spiderlings doing magic damage is a massive buff to her damage overall because most of the items that she builds include magic penetration, so before when the damage was falling off due to it being physical, now it doesn't because you're building resistance penetration for it. Plus that bug fix is a massive damage boost because if you rappelled on a target you lost about 3-3.5 seconds of damage on that target from the spiderlings not attacking.
Pair that with the fact that she had tremendous mana problems in the jungle, and Runeglaive came out eliminating that problem, she basically just has virtually unlimited sustain in the jungle after completing runeglaive.
Don't get me wrong the stun gaining a whole .6 seconds is great, in fact it's huge, .6 doesn't seem like much, but you can throw out a whole lot more damage if the enemy is unable to go anywhere for a half a second longer. The stun improvement isn't the major thing though.
She's likely to get hit by the nerfbat, because her buffs paired with the AP item changes made her a complete monster, not that I'm complaining, I love my spider queen.