As many do appreciate you MROOGLing for us, those links, if you bothered to read them rather than post without any help toward this discussion, don't do much for the OP's thoughts.
First, the links weren't for you, but for the OP. Second, I did read them. The OP asked:
Why does everyone hate it so much?
Those links are perfectly relevant, as they give people's opinions that the OP asked about.
A few of those links give no actual numbers of usage like gaming FPS etc.
The OP didn't ask for actual numbers of usage; only why people didn't like the 6490m. Again, they're relevant.
Also some are old and unsubstantiated, like saying the 330m is a way more powerful card.
All those threads have posts within the past 5 weeks, so they're not old. As for unsubstantiated, again, the OP didn't ask for that. The OP asked why people hated it. Those threads are directly relevant, even if you disagree with the reasoning of some of those posters.
Please don't just come into threads and post links when the links themselves don't really add much to a specific topic question here.
I'll post what I like. The threads are current and relevant to the OP's post. If the OP wanted something else, they should ask for something else. The links were posted as relevant reading, which they are. They're not intended to be a replacement for this thread, or a guarantee that everything that is discussed here will be addressed in those threads, to everyone's satisfaction.
You post your way and I'll post mine.