Nintendo 2DS is a curious system. Launching on October 12, just in time for Pokemon X & Y, Nintendo's budget entry into the 3DS family gets rid of the long-running clamshell design and, most notably, 3D support. At $129.99, it's $40 cheaper than the standard 3DS.
Although the clamshell design is missed, the 2DS is not the monster many had assumed when it was first introduced. In fact, the 2DS is perhaps the most comfortable model to use, simply because it's easier to grip onto. The system is larger than the 3DS, but much lighter than the 3DS XL, making it the most comfortable 3DS variant to hold. (The original 3DS was a bit too cramped, while the 3DS XL can be a bit heavy over long periods of play.)
As the 3DS library matures, it's clear that the lack of 3D isn't a particularly huge loss. With the odd exception of Super Mario 3D Land, very few games--even from Nintendo first-party--encourage moving the 3D slider to "on."
It's comfortable, it's cheap. It's not just a great entry point for the 3DS ecosystem--it's a worthy member of the 3DS family. If there's one thing that could be improved upon on the 2DS, it's the size of the screen. After getting accustomed to the 3DS XL, the 2DS feels much too small. Of course, that's a problem that can be easily rectified if Nintendo ever decides to announce the 2DS XL.