I dunno about that. Being a pretentious a-hole has its upsides. I mean, why else am I ever on this site?

I have never online gamed (at least on broadband) on anything other than WiFi, and i've never noticed a problem.

Unless you're like runqvist and live in Finland (damn, now i'm rather jealous of them), your actual ISP speed will crap out long, long before your WiFi does. I have 3 Mbps internet at home and Wireless G which is being bottlenecked by Verizon.

I'm starting to feel the "serious" part of "serious gamers" is for "serious money problems" for not being able to buy a 10 dollar accessory.

the problem is if the teammates/opponents also buy that $10 accessory ...

if not you might have a good connection, but it doesnt really matter if you opponents lags in front of you or if you play games like street fighter and your inputs are messed up ...

but it shouldnt matter if you dont have the wlan router at max range so that your latency will get heaviely influenced ...
but some appearently have it that way and it feels pretty lagy, but most of the time games over wifi are playable.

but if you already have bad connection or just good enough connection like 100ms and then both using wlan which are not positioned optimal you can add 50ms for each player which might end in 200ms ping which might be bad (numbers just for e.g.)

Contrary to what some people here think wi-fi works and Wii U has the best protocol available! You can play games lagless with it and doesn't need a 10 dollar accessory for most cases - if your connection sucks it'll suck with or without it.

Otherwise people wouldn't be playing Vita/3DS or watching HD Movies on iPad.

yes wifi works most of the time especially if you have good connection ... but sometimes it doesnt work (rarely) if one/both had wifi
but after switching to wired it became 'playable'. but those persons already had not optimal connection (isp) to work with in the beginning and the wifi was the trigger.

in countries where you have pretty good isp like asia/some parts of eu you will do fine even with wifi, but if you have shitty isp like us/australia and your wlan router is misplaced it might be better with wired then wifi. 

also hd movies 'ping' or latency really doesnt matter as long as the speed is there. and the games for vita/3ds < what games are there that you can play online which heaviely depends on latency ? are there some fighting games that you can play online ?

You can watch movies with lag though. Playing games with lag is difficult.

Wifi is not as smooth as a cable is, be it 2012 or 2020. Yeah, one can get a usb ethernet but that is kind of silly to not being included in the first place.

Well, I say this all the time.
If it's that such a problem for you, don't buy the system.

I believe it won't be a hassle for 98.3% of the consumers and the ethernet adaptor will solve some 1% more for those users, bringing the total of satisfied users to 99.3%.

If you're one of the 0.7%, really, don't buy it, but also stop saying it's a big problem.

I largely agree with this, the only thing is that latency compounds, so if your ISP lags and you're on a laggy Wifi, it's double the suckiness. Ultimately Viper's solution should help the wifi lag, but the ISP lag is another ball game (might need to change service providers). I admit that a wired connection removes any worry of possible lag from a poor Wifi connection.

You should be jealous of swedes, they have 1gb connections coming widely available. Will be a while before those speeds are widely available in Finland...

http://www.bredbandsbolaget.se/bredband/hastighet/bredband1000/index.html

Well I am not very jealous, because of the price. I have a 100mbps connection free as in included in my maintenance fee and 1gb will cost 20€ extra. It will be cheaper than my 350mbps cable connection.