The good: All features work as advertised with no surprises. It switches between docked and undocked modes almost instantaneously. The joy-con controllers are really good. Having two in the box means you can play multiplayer games on day one without having in invest in extra hardware. The system itself feels sturdy and well constructed. Nintendo first party games! (IE the reason you buy any Nintendo product). Mario is a blast, Zelda is mind blowing, Mario Kart is stupid fun. You know what you're going to get with Nintendo games. The indie game support has been really impressive! Nintendo has seemed to focus on quality rather than quantity with its indie offers. From games such as Overcooked, Stardew Valley, Golf Story, The Sexy Brutale, you're going to be able to find games you enjoy at cheaper prices, and support developers who aren't EA.
The bad: The joy-cons are not as comfortable as other controllers for longer play sessions. The pro controller (an additional cost) is recommended if you plan on playing the Switch at home with games such as Breath of the Wild. The Nintendo online features are somewhat lacking compared to Playstation, Xbox and PC gaming. Friends lists are a mess, you cannot send messages or game requests through the system. To send a friend request, you cannot search via name, but have to send through a 12 digit code to your friends via SMS or another messaging service. The friend system seems really archaic for a system released in 2017. Voice chat can currently only be done in one game (Splatoon), and is handled through a smart phone. That's right, you don't do voice chat through the system, but through your smart phone! For this privilege, Nintendo will be charging you $30AUD a year to access this service (despite discord being available on mobile for free).