Generally trademarks are limited to specific wares in the trademark application. so, for example Transformers Prime Trademark:
http://www.cipo.ic.gc.ca/app/opic-ci...tIndexOnPage=1
Protects the following wares and services:
WARES:
(1) Toy action figures; toy vehicles; toy robots convertible into other visual toy forms; board games.
SERVICES:
(1) Entertainment services, namely an on-going animated television series.
Computers or Tablets don't fall within that definition, and therefore the use of Transformer Prime for the Asus Tablet shouldn't really be a violation of Canadian trademark. Not sure about US or international rules.
I'd like to see a copy of the lawsuit filing - see what they're claiming.