He also proved several time that he is right.

Tamaki does have sources at devs, but he doesn't really within Nintendo it looks like. 

This guy has a source within NOA and has proven it with two confirmed leaks. 

Basically he's leaked the 3DS release schedule, Pokemon Niji (Moon/Sun codenames), Disney Art Academy.

With regards to Wii U he's said only one unannounced title from Nintendo for Wii U this year (probably Paper Mario), a Minecraft-Nintendo collaboration for 2016, and Zelda U/NX is multiplat with NX launching this fall. 

Beyond that Paper Mario U, Zelda U (even if its not exclusive), Pokken, Star Fox Zero, SMT x Fire Emblem, and a Minecraft collaboration of some kind is not exactly a bad year for the Wii U anyway. If Tamaki said the Wii U would be getting more software he wasn't wrong. 

Yes, but last couple times were wrong. Also source for this rumour has verified by Neogaf,  and few things from that rumour are already proved like right.

What I've actually saw (in the NeoGAF thread, so the only source that has been approved) is that he only leaked the full 3DS lineup, some marketing/budgets stuff and nothing else. He hasn't even detailled the Wii U lineup like he did with the 3DS, that could mean that he's not completly sure about the Wii U lineup. Also, I doubt there's only one Wii U game left (let's say it's Paper Mario, most likely), I'm not expecting a ton of them but at least one or two more budget titles.

He didn't detailed Wii U lineup because there is nothing about WIi U lineup left, only left one unannounced Wii U game. If NX home consoel is coming this year there is no point to have strong Wii U lineup.

He got bought Wii U and 3DS infos from same source.

yup. seems like it was accurate info. really interesting. I am excited for the NX. I REALLY hope nintendo has learned from their recent missteps/mistakes/terrible decisions with some things.

I've read multiple rumors about more than one Wii U game left to be announced (in addition to Paper Mario, which's a lock for me). I still have some doubt. We'll see ! At least, it's good to see that NX is coming this year and Zelda too.

Yeah, it comes off like the Nintendo legal department spooked him.  If I were him, I'd have probably done the same thing since he's just doing all of this as a hobby and the legal implications/potential headaches wouldn't be worth the trouble of keeping the videos up.

Yeah the videos being yanked actually makes them more credible. There are hundreds of vids of guys randomly saying Nintendo will do X/Y/Z on Youtube ... why are Metal Dave's videos the ones apparently gone? Looks like Nintendo told him to take them down.

Yeah it all seems likely now given what we've heard the last couple of days. Interesting. Scary stuff, rumours that are going to become truth, what world is this? What are the ninjas doing?!