It has been confirmed 100% that the XB360 is moving to a 60g HDD standard. Those configurations are in design verification testing right now.  It is said that this changeover also contributed to the lack of units. When Microsoft changes major sub-assemblies like this, they try not to over produce the old configurations.

This is a very great time for 360 current owners and people who wish to own a 360. How you ask?

Current owners of 360s:

1. The 20gb will probably move to arcade and 60 gb as premium (meaning game developers can add cache to all their games). Faster loading times are always great.

2.Bigger downloadable content. Well the PS3 has a larger "sized" disks but the 360 has the ability to store half of a game on a HDD. Meaning LONGER gameplay on newer games.

People who wish to own a 360:

1.  Lower prices on all 360s (especially with the new chipsets around the corner).

2. Blu-Ray on 360? Get ready….it is not confirmed yet but it is almost very positive now that HD-DVD is out the door.