Olight makes good stuff, and as importantly has decent customer service. This knife like c7m2p3 said, it's a great way to get more people interested in knives. I agree that sticking "O" in front of everything is a goofy Apple-like marketing thing.
Murdermook is 100% right that some of their lights get really hot, but at their average price point you can't get fancy heat dissipation AND super brightness- also they are now starting to take care of this with proximity sensors that turn down/off the light if it detects this going on.
They are a really innovative brand- their LEP weapon light is a good example, unlike an LED it can throw a tight beam a couple hundred meters. If you haven't seen an LEP light in person, it's probably something most people here would appreciate.
Even the little bulbs (sorry, "O"bulbs) they started selling are neat little gadgets- very strong magnetic base, waterproof, and 4 very useful modes. I am finding myself using it almost daily.
I bet their next knife will be something much more interesting, this is their modus operandi- they put something out there and pay attention to their customers' feedback to make it better. I don't have any of their pens, can anyone say whether or not their second pen addressed a lot of the complaints from the first?