Apple this morning sent out invitations to an event in San Francisco on Wednesday, September 7. The invitations said: "1000 songs in your pocket changed everything. Here we go again."

Apple is implying that this is the biggest thing since the original iPod (which held 1,000 songs).

What could that be? Top candidates:

1. An increase in the capacity of the iPod shuffle, and possibly the iPod mini. If this is it, then Apple's invitation is over-hyping the event.

2. Color screens on the iPod mini. Again, unless there's more to it than this, Apple is overselling it.

3. A video iPod. This could possibly fit the description, but it isn't even known with absolute certainty that Apple is working on it.

4. A phone that would sync with iTunes. Motorola is known to be working on such a product, and it is overdue for release. This could also fit the description, and is known to be in the works; Motorola CEO Ed Zander said on July 25 that the iTunes phone would be released before the end of September.

5. Some other wholly new product that will either replace an existing iPod or iPod series, or add to it. Usually there is some rumor-mongering going on, and all rumors I've seen are covered by 1 through 4 above.

6. An overhaul of multiple iPods, e.g. bigger shuffles, color iPods, lower prices. This is a distinct possibility.

However, my bet is on #4 since the phone is known to be imminent, and because it is something completely different than other iPods. There is reason to doubt this however: Motorola has not made a similar announcement to Apple's, and Zander said they would make a joint announcement. We'll see.

But I have to figure out whether I'm serious about that. I was planning on exchanging my ailing iPod for an upgraded model on Labor Day (2 days before the new announcement). It could be advantageous to wait. On the other hand, it could be advantageous to jump now, since my trade-in credit is price-based, and my trade-in value could drop on September 7.