Are you talking about US here, or are you talking about the LucasArts.com forums?
I'm sorry I haven't been watching this one very carefully.
Generally, reasons for locking threads are as follows:
1) Flaming and Trolling. Good topics can be derailed when people resort to fighting and repetative arguments (real debates go in forums like the "Senate Chambers" when possible).
2) Multiple posting. I'm talking here about people not just duplicating threads, but also posting the same exact topic instead of contributing to an existing one on the same subject already. More often than not however, threads are merged. If it's just one post or something, the mod closing the thread will usually post a link to the topic and urge the thread starter to take the discussion there instead.
3) Spam. Pointless threads that have nothing to do with the forum or are intended merely as "flame bait" (similar to #1).
Topics posted in the wrong forum are generally moved, or sometimes (rarely) they are locked with a suggestion of where to take the discussion (to the appropriate forum).
I know of no "conspiracy" to suppress legit information about the game here. The only general rule we have is that if you're asking for CD cracks or how to pirate the game, you'll get warned, possibly banned and your links/posts edited or deleted. Since this game isn't really story-based, spoilers won't be edited, unless they cross over, say into Episode III movie spoilers for example. And again, that's an edit, rather than a lock.
Hope that helps to clear things up. If you feel that something has been locked unfairly or have some beef with a moderator, feel free to contact me via PM or another Admin and we'll do our best to get things straightened out.
Keep in mind also that this forum is for GAME FEEDBACK, there is also a forum for feedback about THIS FORUM (swbattlefront.net) which again, I should remind everyone is fan-based and fan-run (not part of LucasArts.com). We have no control over what goes on over there, and they don't have any say in what goes on here (beyond say, complaining to us if we allowed people to spread warez or something like that).