Wii 8/10
DS 12/10

Snes 11/10 best system ever IMO.

N64 5/10 I got it late in the cycle and don't have very many games.

GC 8/10 It's the system I have the most games for and most of them are great.

DS 7/10 Great system but I lack games for it right now.

Wii 9/10 I can still play my GC games on it and the new games that come out are great.

Phew boy, I had to go all the way back to my second post to get my list. It's tough, but I'll rate them.

1. SNES: 9.4/10

2. Genesis: 8.6/10

3. TG16: 7.5/10

4. NES: 8.8/10 (actually I bought this much later, but my list got screwed up a bit and I just can't be bothered to re-position it).

5. Gameboy: 8.5/10

6. Gamegear: 8.0/10

7. Jaguar: 0.00001/10

8. Saturn: 5.5/10

9. Nomad: 2.7/10

10. PS1: 9.8/10

11. Nintendo 64: 9.2/10

12. Gameboy Color: Same as Gameboy

13. Dreamcast: 8.3/10

14. Playstation 2: 9.6/10

15. Gamecube: 8.1/10

16. Xbox: 7.2/10

17. GBA: 6.4/10

18. Wonderswan Color: WTF/10

19. PSP: 9.1/10

20. DS: 9.0/10

21. Atari 2600: 8.2/10

22. Wii: 8.7/10 (of course, it's new, so the score may get better or worse as time goes on)

23. Virtual Boy: 1.5/10

24. Xbox 360: 8.7/10(of course, it's new, so the score may get better or worse as time goes on)

I really can't decide between the 360 and Wii. Both are great consoles. That said, I used a reviewer's scale and I'm not ashamed of it. 

N64 - 6/10
Xbox - 7/10
X360 - 9/10

Game & Watch (Zelda) > 4/10
Nintendo Entertainment System > 7/10
Game Boy > 5/10
Super Nintendo Entertainment System > 7/10
Virtual Boy > 3/10
Game Boy Pocket > 5/10
Nintendo 64 > 8/10
Game Boy Color > 6/10
Game Boy Advance > 6/10
Nintendo Gamecube > 10/10
Game Boy Micro > 10/10
Nintendo DS > 9/10
Nintendo DS Lite > 8/10
Wii > 9/10

wii: 10/10
ds: 10/10
gamecube 8.5/10
snes: 9.5/10

I'll only list consoles I've had a lot of experience with (so even though I owned an NES, GBC, and a PS1, I'll ignore them).

N64 - 9.5 - Some of the greatest games of all time (including THE greatest game of all time, the Ocarina of Time), but they were few and far between.

PS2 - 10 - Much like the N64, it had some of the greatest games of all time, but plenty more on top of that!

GC - 8 - I bought a GC pretty late in it's life (when it hit $99), but it kept me quite content between SMS, SSBM, LoZ: tWW, and other games. It had some awesome games, but it didn't compare to its awesome predecessor, the N64.

Wii - 9 - The premise is awesome, but the controls haven't been utilized quite as well as I'd hoped (yet). The awesomeness of TP, SMG, SSBB, and MKWii still warrant a 9, however. And then there's the Virtual Console. :D

PS3 - 8.5 - Games like Uncharted have been excellent, but overall the software library is somewhat lacking (particularly for someone who cares little for GTA). However, Blu-ray has been awesome, and the ps3 in general is a beast of a machine. This in combination with what games it does have warrants the system an 8.5, but with MGS4 hitting in two days and in-game XMB just a week later, it should be a 9 very soon.

DS - 9 - This is my most recent purchase. I'm currently addicted to Pokemon Diamond, and I still have Phantom Hourglass, Prof. Layton, and others waiting in the wings!

PC - 9.5 - What can I say, it's the PC. This would be a 10 if I hadn't run into so much trouble after upgrading (if you want to call it upgrading) to Vista.

"7. Jaguar: 0.00001/10 "

Hahaha. Was the Jaguar that bad?

Wii | A-
DS | A-
SNES | A-
GCN | B+
N64 | B-
GBA | B

Hrm, I am thinking of upgrading Wii really soon though. As soon as Kid Icarus, Zelda, Animal Crossing or HDD are unveiled...

360- 9 lots of games great online. annoying hardware and online cost
ps3- 6 few games but overall weak library, annoying controller, free online
wii- 6 few good games love twilight princess and galaxy but mainly sequels of games i liked on 64/ gamecube and weak online and graphics

obviously current gen numbers can change

DC- 10 just loved everything about that system
SNES- 9.5
PS1- 9
N64- 8.9
Genisis- 8.5
ps 2- 8
game cube- 5.5