The DSi XL is just like the DSi except it's bigger.  In Japan they released it as the DSi LL, here in the states we get the DSi XL.  XL just stands for Extra Large.  What that brings to the table is a device easier and more comfortable to use for most kids and adults.  The text is bigger, there is more room to write when needed and even someone with big hands can push the buttons with their thumb and not have to reach for the stylus as often.

 

Is it worth upgrading to the DSi to a DSi XL?  Well, the screen is bigger and because it's bigger it seems to look brighter.  It's comfortable to use.  It works the same as a DSi.  I guess it all comes down to you at the this point.  Do you ever have to wear glasses to play your DS or DSi?  Do you get hand cramps?  If so, then maybe this is for you.  If you like something more portable that you can fit in your pocket, well then you probably want to stay with the original DSi.

 

Hope this helps in your search for the right portable game system.  Click the link for more details about the DSi XL.  You can find reviews there too.