I have to throw in my few bucks here.
I'm going to start out by syaing that Deadlands is my baby, and that it is the game of choice to bring new people to the table.
When I heard that DL d20 was coming out, I fealt that it was going to threaten the entire Deadlands Line.I found that it lacked many aspects of Deadlands that brought it fame and uniqueness so many years ago. Deadlands has the feel of an old west game of poker, and the d20 version just fealt like D&D with guns n' nuns.
I do understand that it is a great way to bring new players to the game, but I feel that they would be very hesitent to change, and that some people might actually think that DL d20 is the true form of Deadlands (icky). I have found that d20 adaptation is pretty good for some kinds of games, but is really bad for some others.
That said, I think that the d20 material (now in HoE and LC) could potentially be put to some good use (and not as toilet paper). Almost everyone is familiar to some degree or another with d20 rules. Those new to Deadlands who chose to go the classic route, could use the d20 material as referance to help learn the newer rules set; understanding the underlying concepts from the d20 works and simply doing them a slightly different way. A good example of this is figuring out TN's and DC's.
Now that that is said., I will move along to Lost Colonies. Myself, my best friend,and a number of other's I have talked to have all been waiting for LC to come out since we saw it in the HoE book (3ish years back). I'm glad that it is now out. I do think that it feels a bit empty. I'm not sure if it is because is is new, or if there is another reason for it. I think a good way to "untarnish" LC's good name is to have some more material out and fully support it. That way, people don't think that LC is being underemphisized compared to DL and HoE. As the saying goes, "If you build it, they will come." At the very least, people will buy it and play it simply because it has the Deadlands name on it (Final Fantasy anyone?).