Nintendo is usually last among the big three gaming publishers to announce a price drop, as evidenced by the DSi, which has gone since its launch in November 2008 at its current price of $169.99. Nintendo will be dropping that price on September 12, bringing the standard DSi down to $149.99. The DSi XL, the newer, larger cousin of the DSi, is also getting a price drop on that day: From $189.99 to 169.00.
Obviously the important thing to ask is Why? The lower price will undoubtedly increase sales over the holiday season, which is exactly what Nintendo wants in the months leading to the release of the 3DS. After all, the moment Nintendo releases the new 3D handheld, sales for the DSi and DSi XL will probably take a nosedive, so they're better off getting while the getting's good.
So where does that leave you? Should you take advantage of the new price drop or hold off for the new handheld in 2011? Well, that all depends. If you already own a DS Lite, and it isn't on the verge of death, I'd say you should just hold off until the 3DS, which has all the features of the DSi, plus a whole lot more.
If you're without a handheld gaming console and you think you're going to need one between September 12 and next spring (which is when the 3DS is projected to release), I'd suggest going with a DS Lite, which remains at $129.99. Most people don't use the bells and whistles of the DSi and you're really just looking for a stopgap until the next big thing.
Of course, that's just my opinion. This is your money we're talking about.