What is the feasibility of offering game bundles on the TTG web shop containing the PC/Mac versions along with redemption codes for the console versions?
I think it would be extremely convenient to TTG's customers to offer, for example, the PS3 version of The Devil's Playhouse in the web shop. It could be discounted if you already own the full season of the PC/Mac version*, or offered as a bundle with the full season if you don't.
There's also the option of offering the console versions separately, but since I'm not familiar with the pricing or feasibility of producing redemption codes, I'm under the impression that it may be easier to just let those purchases occur through the PS Store/Xbox Live/iTunes, rather than waste codes.
I'd say $10 per upgrade would be fair, but pricing is completely up to Telltale if they decide to do something like this; $10 per purchase may not be able to cover the cost of distributing a copy of the console version.
* This would be in the same vein as the Season Upgrades, where if you already own one episode, you could get the rest of the season at a discount; if you already own the full season of TDP, the PS3 version would appear as an upgrade.