On this subject you have to take the useful with the self-interested to some degree. On balance, I'd rather have most of the manufacturers who've contributed here provide their knowledge and insights, as long as they identify themselves and 'keep it real' by posting in an honest, even-handed way, not attempting to manipulate discussion or overly promote their own viewpoints/products, while answering questions that are asked of them and consenting to participate in give-and-take, back-and-forth exchanges.
As some have found out, any manufacturer who dares to post in the forums runs the risk that they might alienate as easily as impress, or wind up with a no-win argument on their hands. On the other side, there's always the supposition that any publicity is good publicity. I've been told it can be tough not to react badly in response to some of the nonsense that's sometimes said about companies, products, and technologies in an anonymous online environment.
IMO only manufacturers with the right temperment and commitment are well served by venturing into the forum waters; just dipping their toe in, or feeling they must respond to every 'challenge' even if they're not the diplomatic type, is just as bad an idea as entering the forums simply to spread propoganda -- it's asking to get burned. I also think it's probably best for manufacturers not to participate *too* much -- not to try to be 'one of the guys' and yak it up here on 10 threads a day, or to get too humorous too often. A little goes a long way with manufacturer participation, and if they're too ubiquitous or chummy it might give the impression of pandering, so it's wiser to ration commentary and stay mostly on-topic regarding relevence to their own products or areas of expertise. (An exception is posting about music as opposed to gear or tech -- I think manufacturers can post about music just as any member would.)
I know plenty of manufacturers read along while preferring to keep discretion the better part of valor, or maybe some hold a principled belief that it's best not to 'interfere'. And I'm sure there are plenty of others who simply don't have the time to give. But IMO the ones who can do it well potentially help themselves *and* everybody else -- ideally the two aims are not incompatible. I know I'm always left with a more favorable impression of anyone who communicates openly in a worthwhile manner, even if I don't necessarily subscribe to all their ideas.
