A smorgasboard of downloadable content and on-sale items will arrive on the PlayStation Network today, joining the two already announced PlayStation Eye titles. Usually arriving on Thursday, the store received its update early due to the Thanksgiving week, as detailed in the official PlayStation blog.

Most notable are the Rock Band (PS2, PS3, X360) downloadable tracks, which are already available on Xbox Live and listed in our post earlier today. Every track from the Xbox update has made its way to the PlayStation Store as well, with prices of $5.49 for the three-song Police, Queens of the Stone Age, and Metallica packs. Individual songs are priced at $1.99.

For a holiday gift to PS3 owners, Sony cut the prices of three notable titles in half and reduced the cost of another, making each in the lot available for $4.99. The sale comprises Queasy Games' Everyday Shooter, thatgamecompany's flOw, Incognito Entertainment's Calling All Cars, and Q-games' PixelJunk Racers and will run until November 29.

A 714MB demo for Rainbow Studios' upcoming MX vs. ATV Untamed (PS2, PS3, PSP, NDS, Wii, X360) also arrived on the store, the same one that arrived on Xbox Live earlier today. The game hits stores on all platforms December 17.

Additionally, a flOw expansion pack has arrived for $2.99 that extends the original game with a new campaign and new creature. It also includes a screenshot feature.