360 is going to be very attractive for gamers and families this Christmas.

There are tons of games for $19.99-30 (about 150 available on Gamestop)
A $199-$299 price tag.
RROD has been pretty quiet recently.
They have decent third party controllers for $25.

If you put value/budget games and accessories into the equation (which Christmas shoppers do) then 360 is an incredibly good value. I think 5 is completely possible and expected.

(BTW, I think all three consoles are a terrific value)

I was going to put this in a Microsoft Value Game thread, but I think it is relevant.

Under $20 at WalMart:

1. Viva Pinata
2. Saint Row
3. Lego Star Wars II
4. Sonic
5. Crash
6. King Kong
7. Beowulf
8. Spider Man frien or Foe
9. Looney Toons
10. Ratatouie
11. Spider Man 3
12. Fusion Frenzy
13. Jumper
14. DDR
15. Conan
16. Stuntman
17. Pirates of the Carribean
18. Eragon
19. Bomberman:AZ
20. Overlord
21. EDF2017
22. Open Season
23. Kameo

Under $30

1. Assassin's Creed
2. Naruto
3. CSI
4. Marvel UA
5. Transformers
6. Dead Rising
7. Bully
8. Avatar
9. Bee Movie
10. Simpsons
11. Bullet Witch
12. Crackdown
13. Spiderwick
14. Shreck
15. TMNT
16. Lost
17. Golden Compass
18. Harry Potter
19. Fantastic Four 2
20. Meet the Robinsons
21. Bionicles
22. WWE

Not to mention all the Used games.

The rumored pricing for 360 is $199/$299/$399 vs. the current $279 & $349/$400/$480.

Doing some math...for the last three months I think we can expect:

360 ~ 13k/week avg * 13 weeks in Japan

        ~ 115k/week avg * 13 weeks in Others

       ~ 230k/week avg * 13 weeks in Americas

4500k ish in sell through for the last quarter so 5m+ shipped seems likely...