"Is this when the warrants will be tradable on their own?"

Not sure. Normally, when share/warrant units are distributed to your brokerage account, they will sit in your account as "units" for a few days. Then the shares and warrants are separated and they trade on their own.

That may or may not apply here. I see this in the announcement:

Each Subscription Receipt will automatically convert into the Underlying Securities at the Escrow Release Time, subject to the Company satisfying the Escrow Release Conditions prior to the Final Escrow Deadline (March 30, 2009). A Subscription Receipt will only convert into Underlying Securities pursuant to the foregoing automatic conversion mechanism and will not be convertible upon any act by the holder.

Don't know when that Escrow Release Time would be, and I don't know what the Escrow Release conditions are. That should be detailed in the prospectus when it comes out (around Feb 2).