I'm not a coder so I don't know.
I just meant as a general piece of hardware it's not impressive. Not a next-gen leap in power, boring/dated/messy UI, a slow OS, etc etc.
Utter rubbish.
I don't agree with this at all. To each his own (obviously), but the UI is hardly "boring" or even "messy". Wara Wara changes everyday, with the most popular games being spotlighted along with gamer communication going on about that title. That has already proven to be a powerful and useful tool, with many gamers picking up ZombiU even after polarizing reviews becuase of the overwhelming positivity on Miiverse. The menu on the Gamerpad is barebones, but all the media you need to jump into is literally a touch or swipe away. The same can't be said for either the last generation consoles (which sometimes require an extensive search process to access some media), and it is a step up in that regard. Could it be better? Sure. In a better world the Gamerpad would have a Vita-like setup that is more appealing to the eyes and allowing more customization.
Miiverse is nice to doodle around with, brag about gaming accomplishments, and have brief conversations on games, but it really shines when needing a question answered or help with a certain game. Being able to post a picture of the problem you are having along with a description while pausing the game is easy to do, as well as jumping back into your game while waiting for an answer. Through personal experience, answers are giving quickly and most users seem to be very helpful. The same can be done with the Internet browser to look for a FAQ or answer, where your current screen can be displayed on the television for easier access. Could these be better? Well yes. More opitions within Miiverse would be nice along with much MUCH quicker loading (which is a must) would go a long way in approving the experience. Also, the gamerpad home button pulsing green instead of blue for miiverse notifications would have been a nice touch. But right now nothing else quite like miiverse is offered on other gaming consoles, and Miiverse integration within games such as NintendoLand can make for a much more lively and connected experience.
Other features such as being able to access the EShop while pausing a game, and downloading software, apps, updates, etc. in the background is a huge step froward (that will undoubtedly be matched by 720/PS4). Then you have the ability to play games and use apps on the Gamerpad (with the majority of software/apps not even needing a TV) and all the new gaming possibilities/intuitiveness the Gamerpad offers, which are features that probably won't be matched be either of the other next gen consoles.
Nintendo being Nintendo, the WiiU is missing some key features such as party chat, achievements, video chat being mostly useless as an app that requires you to quit your game, weird quirks like needing to access Miiverse for messages, etc. though I think the major issue (right now) is the slowness of the whole thing. But even if that can't be fixed, I still wouldn't call it "utterly rubbish".