1.His wards seem to be changed completely, it's different when you try to block with them, sometimes they do block sometimes not.. The collision size is strange I guess. Creeps can get through his wards even when there is absolutely no gap in between, they walk "through".

2.Also they are castable at the outer edge of the map:
venwards.jpg
(wards planted at such positions give massive higher-ground sight)

3. Another issue is that the camera sometimes gets stuck when moving along those outer edges mentioned in #2. You need to use F1 constantly and move out of the hero to get out, then the camera is movable again.

4. It's possible to get stuck using blink dagger in this corner (and probably others too), you can move the camera freely over the map borders then, your hero gets stuck half - no movement possible but casting boots of travel or veno ultimate is possible.
veno2.jpg