I've added the Syfy trailer to the Trail of Blood page as well as updated the episode descriptions.

I've also added a new episode description for Hero II.
I've added the Syfy sneak peek for episode 4, Trail of Blood. Tesla's back!!
The Henry episode that we've been hearing about is episode 6 - Animus and Hero II has a subtitle : Broken Arrow. Here are three more episode descriptions for you :

Trail of Blood
The team gets a cryptic distress call that could only come from one person. Nikola Tesla. The team heads off to respond to the call, but Will has his suspicions as to Tesla's true intentions.

Hero 2: Broken Arrow
Will and Kate are hijacked at gunpoint while transporting Abnormals to an off-site storage facility, but the gunmen aren't looking for money.

Will and Henry travel to the UK to follow up on a werewolf sighting and end up uncovering a dark connection to Henry's past, and to his future.

Source : SciFi Channel (Aus) - Sanctuary website
By now you have all seen Walter "The Adjuster" from last year's episode Hero in the S3 Trailer and Chris Gauthier has just confirmed that he will be appearing in the 4th episode this season.
According to SciFi Channel Australia's website the new Season will premiere on 21-Oct-10 at 8.30pm. Also it has episode 4 listed as Trail of Blood, see the episode page for all known spoilers so far.