PS3 Goods:
Very robust media player
Fantastic build quality
Some very high production values in certain titles
No more memory cards \o/
Wireless controllers
I also like the fact that i know the company that built it spent more making and shipping it than i paid to buy it, guess you could say i feel i got my moneys worth.
PS3 Bads:
The fact that firmware development seems to have been a completely detached entity from hardware development, until recently at least.
No headset supplied
High production values lead to long production times and high costs.
Delays, delays and more delays.
Wii goods:
(things like wireless that also apply to ps3)
Innovative control method
Its small?
Wii bads:
Lazy developers cashing in without any imagination or creativity
IMO not a single really good game has been released for it yet
It could have been so much more (and might one day?)
Batteries, i hate changing batteries.
I don't own a 360 (yet), so no positives or negatives there, other than the fact that the wireless adapter is too expensive for my mate to buy so whenever i go over there its offline playing only

.