There are four Different Kinds of Xboxes currently being manufactured- But which one is for you?
4G
4G means 4 Gigabytes of Memory- Which isn't a lot.
4 "Gigs" is only enough space for about 2-3 games, and that's if you don't want to play online. If you had more memory, you could download games, demos, Indie games, movies, songs... But 4G isn't really enough to do all that. I recommend this for college dorms, or other places where you are just going to buy one game and Play that one over and over until time stops.
What you get; Free Month of "Live", 1 Controller
200$
250G
250 Gigs is 250 Gigabytes of Memory- Which is A LOT. a 250 Xbox is for people who like to download games instead of going to the store, people who play lots of different games, people who like to download free games, movies, and demos.
I recommend this for Hardcore or Family gamers- You could probably get 5 years out of this memory, and you could always add more memory.
This is the rarest Xbox, but I completely recommend it if you don't want Kinect.
What You get: Free Month of "Live", One Controller, Headset, Demo of MW2
300$
4GK
4GK- Or, 4 Gigabyte Kinect, is the same thing as the 4G system except it includes Kinect in the package. Kinect is for families that are into the whole "You are the Controller" thing, and you must have a lot of space to play it. Kinect is fun, but with 4G you don't really have that much space to play the Kinect games anyway. I reccomend this for people who are buying the Xbox Strictly for Kinect- and Don't plan to have over 3 games.
300
What you get: Free Month of "Live", One Controller,Kinect, "Kinect Adventures" game.
250GK
The God Of all Xboxes- the 250 Gigabyte with Kinect.
With this Big guy, you get a whopping 250 Gigabyes, good for a really long time, and the Kinect sensor. This is for people that will by tons of games, like Kinect, and have people [and the room] to use it. This is the King, if you want to spend the Money- It's probably worth it.
400
What you get: Free month of "Live", Headset, One Controller, Kinect, "Kinect Adventures"
Note; All Xboxes are compatible with extra Memory (250G for 120$), and Kinect(even if it wasn't included) in a separate purchase.