Hardware then:
Xbox 360: At launch, we had the Arcade with no Hard Drive and a wired controller. The premium model came with a wireless controller, a 20 GB HDD, and chrome finish. There was no HDMI support, and there was a pretty good chance that the console would explode and kill your hamster. It cost $299 for the Arcade and $399 for the Pro.
Playstation 3: At launch, we were give two models. There was a 20 GB model with diminished features for $499 or a beefier 60GB model with extra USB ports, Memory support, and Wi-Fi. The controller didn't have rumble. It featured the ability to play Playstation 1 and Playstation 2 games.
Wii: At launch, it was a pretty solid piece of hardware. It featured Wi-Fi connectivity and multiple applications via its "Channels"
Hardware now:
Xbox 360: Now features HDMI support, runs a lot cooler and quieter. Retail models are now known as the Arcade (no HDD) $199 and the Elite (black with 120 GB HDD) for $299 msrp. It will not explode when you turn it on.
Playstation 3: Now features a 120 GB HDD as well. Is now half the price, at $299 for a Slim Model. Controller now vibrates. Backwards compatibility for the PS2 has been scrapped. I think that some of the USB ports have been removed, but I'm not sure.
Wii: Still the same console that we knew and loved. Now it supports memory expansion via SD card support.
My opinion: As far as hardware improvements, I'd say Xbox 360 (+3). PS3 (+2) Wii (+1)
Software then:
Xbox 360: At launch, 360 owners promptly hung themselves........or played Kameo and Call of Duty 2.
Playstation 3: At launch, and for quite a while after, PS3 owners promptly shot themselves in the balls......or played Resistance: Fall of Man
Wii: At launch, Wii owners played Wii Sports or The Legend of Zelda: Twilight Princess. Not too shabby, huh?
Software now:
Xbox 360: Xbox 360 owners are treated to some of the best games that money can buy. Games like Call of Duty 4: Modern Warfare, Forza 3, Gears of War, and Assassins Creed 2 keep 360 owners satisfied. The downloadable games on Xbox Live are in a league of their own. There's always something great to play!
Playstation 3: PS3 owners are treated to the exact same library as the 360! They also get a few great exclusives like Uncharted 2: Among Theives, inFamous, Killzone 2 and Valkyria Chronicles. Surprisingly, the PS3 has turned things around in 2009. Popular opinion is that the PS3 simply had the best games in 2009. What a difference a few years can make!!
Wii: The Wii has sort of stalled out. In the early goings, games like Mario Kart Wii, Metroid Prime Corruption, Super Smash Bros. Brawl, and Wii Fit made the Wii a must own. While great games still come out, it's nowhere near the level of consistency that the other two systems, as far as support. Wii owners are having too much fun to care, though..........right?
My opinion: As far as newly released software, I'd say PS3 (+3), Xbox 360 (+2), Wii (+1)
Intangibles:
Xbox 360: Since launch has added features like HDD install, Netflix, independently licensed games, Last.Fm, downloadable movies and TV shows, Avatars
Playstation 3: Since launch has added pretty much anything that Microsoft adds soon after Microsoft adds it! Netflix requires a disc, and PS3 owners HATE disc swapping, though. PS3 has also added Home. Some love it. Some hate it. Unfortunately, since launch, the PS3 has actually LOST features that it originally had.
Wii: Added several new "Channels" including the Nintendo Channel, Wii Ware, Check Mii Out Channel, etc. SD card support was a very welcome addition. Several peripherals are available for the console too, but they aren't supported as much as I'd like.
My opinion: As far as intangible features, I'd have to say the 360 has added a lot (+3), the PS3 has added MORE but it also lost features (+2) and while the Wii added some pretty neat features, they weren't as impactful as I'd have liked. (+1).
Final Score: It's very close but the 360 is the "most improved". 360 (+8), PS3 (+7), Wii (+3)
Is the 360 the best system? That's in the eye of the beholder. I personally think that, where it counts, the 360 has improved since launch more than the competition.