Exactly! Price, titles (particularly third party), and marketing will be absolutely essential to its success.
Price needs to be extremely competitive. Though the cost to build may be high, Nintendo has a reputation for making value-oriented products. Consumers will still buy a PS4 or Xbox One if they price the Switch at the same level as those 2 products. Not to say it has to be cheap, just competitive. Game titles, and third party in particular, need to be strong to generate interest outside of the Nintendo fan base (which is large, hence why the reveal is top trending on YouTube, but it's not 1/10 the potential target audience).
Marketing. This will be absolutely key. There is potential for this product to fall into a hole similar to the Wii U. Not the same hole, but a similar one. Nintendo needs to market this product solely to the gaming audience, and ensure the public doesn't confuse it for a tablet. Also, emphasize the portability and the stationary benefits, that will be sure to appeal to vast swathes of casual gamers.
They nail these, they'll have a hit without a doubt. "Fail to do so and the consequences may be...severe"-Professor Umbridge.