DS - for history sake, get Goldeneye Rogue Agent.
GC - it actually looks really cool, it's not a bad game, don't shrug it off because it's trying to cash in on the goldeneye game.

- P.N.03 for gamecube is an excellent third person shooter that you should check
- Killer 7 for PS2 or gamecube is also a pretty good shooter on rails with a really cool art direction.
- Geist for gamecube is a very different first person shooter with a great story.
Also, you should try SWAT 3 and 4 for PC. Best tactical shooters I've ever played.

Time Splitters 1-3, RE4 Wii, Metroid Prime 1-3, Killer 7, Geist, XIII, avoid Red Steel like the black plague.

I really enjoyed the first Ghost Recon for PS2, more so then the advanced warfighter series. Missions were actually challenging and require use of cover and tactics. If you skipped over it to play the newer advanced warfighter series you should go back and look into it.

Wolfenstein Enemy Territory.
Not that tactical, but teamplay makes the difference and due to it's nostalgic value it's worth mentioning on a site like this.
For me, and many other as I know from my clan, it was the first online game (card games and such not counted).

Admittedly that is exactly what I did. I'll definitely check those out as well.

Just remembered another series that might intrest you, Socom series for PS2. I didn't actually play this one myself, just watched a friend play it for a while. I also only saw the first out of the series and there seems to be at least two more beyond that. It did look good though and in the same vein as Ghost Recon. One of the key features is giving your AI squad mates voice commands to get them to do things.

I believe Medal of Honor is on PS2.. maybe there's a Call of Duty as well.

There's a Wii version of Call of Duty as well.
COD: World at War got decent reviews for both the wii and the DS, just check metacritic.

Mmh...as an alternative he could try Metroid Prime Corruption. I have it and it's one of the few Wii games worth a thought :-)
And the aiming is flawless ;)

yes the mechanics are quite nice, I've tried Metroid Prime on GC though and did not like it.

OK! I think I should mention something. I did ask for tactical type shooters. In other words games like Metroid Prime, Killer 7, Time Splitters and P.N.03 are exactly what I'm not looking for. Something that requires more intelligence and not just a fast trigger finger and a love of super unrealistic stories/settings.

you have some of the worst systems for games that you want.