Mine too is slightly bent. However, I first noticed it a least a week ago, but assumed it was either part of the deign or "manufacturing variation." Until we see someone document a fresh, out of the box switch warping over time due to the heat, I'm going to assume the bend is most likely due to the same rushed manufacturing timeline that likely lead to the bent docks. As long as this issue doesn't brick the system, or continue to worsen to the point of making the Swirch uncomfortable to hold or make it difficult to put the system in and out of the dock, I doubt this will become an issue for most people.
But I must say, as much as I love the Switch as a concept and a thing I use almost daily, the number of hardware issues are starting to really stack up. The joycon connectivity issue (supposedly fixed now), bent docks and scratched systems, and now possibly this warping issue. Hell, my joycons are even getting a little loose and creaky. Really hope Nintendo gets this stuff sorted out before these issues start to penetrate to the casual audience and tarnish the systems reputation before it gets a real foothold in the market and more developer support.
Really, really glad I bought a replacement plan from Best Buy.