When a co-worker started seriously researching HDTV's back in 2003 or so, he found himself reading some different forums and review sites. I told him then that if he wants to find a product with no negative comments made about it, he could expect to continue watching his early 90's Trinitron for the rest of his life. First, all man-made objects have flaws and faults. Second, the internet provides a largely anonymous venue for people to invest a great deal of time, energy, and angst in flaws and faults. Third, satisfied owners are less likely to go out onto the net and talk about their satisfaction than dis-satisfied owners who are in search of answers to particular questions or problems. It is because of this that all internet research must take place with a cautious eye. Cases where people are strung along by customer service for months on the resolution of a product defect or other specific customer need are something that should be looked closely at, though. The thread with Silverbullet's problems (the one that MinustheBear quoted) includes another worrisome example: two brand new MFW's that exhibit hum without any active source, an issue that was reported to be resolved and that the customer specifically asked about before ordering.
The other factor that didn't significantly affect that co-worker's TV research as much but does have to be considered is personal bias. We all have some bias. None of us have all the right answers. A manufacturer's site will invariably have a number of happy customers hanging around who leaned toward that company's products when they made their own purchasing decisions and will thus tend to advise others likewise. Similar things happen in third-party forums, as individuals who own a product will be more likely to read and participate in threads that discuss the products they already selected. Some will be post-purchase rationalization. Some of it could simply be personal bias. Whatever the case, it can be managed effectively or it can be taken to unreasonable extremes. I post a lot at Outlaw's forum and in AVS threads about OPPO players because I have a lot of experience with both companies, but I try to manage my personal biases. There have long been instances of forum members at AV123's forum and elsewhere who took their rationalization and biases to unreasonable extremes any time questions were raised or unflattering comments were made. That is where Mark's charisma and marketing savvy come into play: he can build up such intense loyalty that people behave that way out of a desire to support their friend. There are always going to be people who see this behavior and are automatically leery of the company and its products simple because of the extreme attitudes involved. For those people, they react initially with the mindset that if it's too good to be true, it probably isn't. Others can get swept up in the energy of some extremes, though, and that's how a new customer base is born. When you've alienated the old customer base as badly as AV123 has, though, you also need to do a lot to keep the old customers (who have mostly traded in their zeal for anger) out of the way...