I'd buy a Wii just for Monster Hunter Tri, it's that good. It's probably gonna last me 200+ hours so I say it's worth a Wii just for that game.
Good RPG's coming out are Xenoblade and Last Story. Tales of Symphonia: Dawn of the New World is already out and I think Tales of Graces is getting localised too. There's also Dragon Quest X.
For action there's Sin and Punishment 2, MH Tri, Zelda (action RPG same goes for MH Tri), Metroid Other M.
FPS's - Metroid Prime Trilogy and Red Steel 2 (very short though).
There's probably more game but I can't remember them atm.

hmmm lets do this

No More Heroes 1 and 2
Legend of Zelda
Monster Hunter Tri
Metroid Prime Trilogy
Red Steel 2 (Motion plus needed)
Mario Kart Wii (mainly for the online its hell addictive)
SSBB (i hate it but he might like it, it depends on tastes really)
Punch Out (if he played the original on nes he might like this)
Madworld
Resident Evil 4
Resident Evil Darkside Chronicles
Dead Space Extraction
Call of Duty MW Reflex
The Conduit
House of the Dead Overkill (addicting game very humourist)
Tatsunoko vs. Capcom
Muramasa: The Demon Blade
Silent Hill Shattered memory's
Scarface
Tenchu: Shadow Assassins

these are the games that are on the top of my head... and how can he hate mario anyway? lol

The Wii is not a good FPS console, the best offer is Metroid Prime Trilogy 3 sweet games for the price of one.

Good titles
Plataformers
Mario Galaxy 1 and 2
Mini Ninjas (cheap and quite good actually)
A boy and his blob (starts easy, ends quite hard)
NSMB
Wario Land Shake it
Mushroom Men (cult classic)

Action/Adventure
Zelda Twilight Princess
No More Heroes 1 and 2
Red Steel 2 (this one could pass as a FPS I think)
Okami (shame for everyone that didn't bought this one on the PS2)
Madworld (another one you could get really cheap)

Fighthing
Super Smash Bros
Tatsunoko Vs Capcom
Guilty Gear Accent Core

On Rails
Dead Space Extraction
House of the Dead Overkill
Resident Evil Chronicles (Both games)

RPGs
Little King's Story
Fire Emblem Radiant Dawn (It's soooo hard)
Paper Mario
Rune Factory Frontier
Monster Hunter Tri

Sports
Mario Kart
Mario Strikers
Tiger Wood
Punch Out

It was worthy since launch day so yes... still worthy!

Get New Super Mario Bros Wii and play together. Fun as hell!

Why can't some people just not like things?  It's not always macho posturing.  While I love 2d mario I would say that all 3d Mario is sub par trash.  And since Mario only seems to sell about 15-25 million I would say there are millions of gamers as well as non gamers who agree with him.

For me, it's certainly more worth it than the 360 or PS3, and I don't like Mario games much.

(and I have a 360, but still buy more wii games than 360 and get far more entertainment out of it... and will probably get a PS3 at some point too..., but the Wii definitely provides the most entertainment)

Let me put it this way. The Wii has more to offer than the GaceCube did already. And there's more coming soon. A lot more.

cool. I guess people can have fun on the wii without mario.and thanks for all the info guys. very helpfull. if he still does not want one then its up to him.

he thinks mario is too gay

do you really think that? I´m not so sure. gamecube had a lot.