EEDAR's Jesse Divnich released a Retail Sales Preview for April, containing predictions for hardware and software sales results for last month. It starts on a down note, unfortunately, with a projected decline in software sales of 17%. "We believe the weak retail environment is to blame for the year-over-year decrease in [average selling prices]."Music and rhythm games got somewhat of a boost in April, according to Divnich, but only because of heavy discounts. "The biggest sales occurred at Wal-Mart.com with certain Guitar Hero World Tour SKUs being discounted by as much as $90 and Best Buy with a sale that gave away Guitar Hero: Aerosmith for free with the purchase of Guitar Hero: Metallica."The two success stories this month are both DS-related. Hardware sales went up over last year, but only because of a new DS launch -- The DS is predicted to be up 129% year-over-year thanks to the DSi. "Without the DSi, hardware sales would have likely been down by over 27%."In software, Rhythm Heaven's "sales performance has been nothing short of amazing," according to Divnich, with sales of around 154,000 copies. The reason? "Nintendo's ability to leverage an effective marketing campaign using a celebrity (Beyonce)." Hopefully some of the people who bought it because they saw Beyonce playing it will then play it themselves. They might like it!