Next crash/reboot or so:

1) "Sleek" wands cast their spells at level 50 instead of level 60.

2) Aura/barrier/shield last longer per casting level.

Essentially, the durations on the sleeks remains exactly the same as they were, and the durations from everything else just got a bit longer, narrowing the gap of how good it is to use one vs. the other a bit.

Edited to add: if you're currently carrying an existing sleek wand that still casts at 60 when this changes over, for as long as it takes you to burn those charges, it's probably like mini mage Hanukkah for you. Enjoy.