Batman: Arkham Asylum has managed to defend its No. 1 position atop Chart Track’s UK Software Sales Chart this week, cracking the skulls of would-be pretenders to the throne, despite a drop in sales of 27%.

Interestingly, the PS3 version of the game is catching up to its Xbox 360 doppelganger, thanks to the launch of the PS3 Slim and a new bundle offering.

Wii Sports Resort (sales down 11%) is a non-mover at No. 2 on the chart, while Call of Duty 4: Modern Warfare (sales up 128%) shunts its way to No. 3 from No. 10 last week, which is incidentally its highest chart position for about one and a half years.

Wii Fit shifts up a place to No. 4 from No. 5, whereas Ashes Cricket 2009 moves down two places to No. 5 from No. 3 last week. Debut charter, IL2 Sturmovik: Birds of Prey, meanwhile, places itself neatly at No. 6 in its first week on sale.

Tiger Woods PGA Tour 10 (sales up 38%) steps up one place to No. 7 from No. 6 last week, as Call of Duty: World at War (sales up 7%) descends to No. 8 this week from No. 6. Fight Night (sales up 68%) battles its way back into the Top Ten to No. 9 (from No. 13), while Dissidia: Final Fantasy debuts on the chart this week at No. 10.

Other interesting movement on the chart this week includes Wolfenstein slipping out of the Top Ten to No. 11 from No. 4 last week, Mario Kart Wii also shifting out of the popularity circle by dropping to No. 12 from No. 7, Call of Juarez: Bound in Blood moving further down the chart to No. 13 this week from No. 11, Grand Theft Auto IV striding up to No. 15 from No. 26, the debut of Champions Online at No. 18, Dr. Kawashima’s Brain Training moving up to No. 25 from No. 34 last week, LittleBigPlanet re-entering the chart at No. 28, Killzone 2 pulling a similar trick at reappearing at No. 30, Prototype falling a long way to No. 32 from No. 16 last week, as Sonic Unleashed and Halo 3 re-enter the software chart at No. 36 and 40 respectively.

The All Formats UK Software Chart Top Ten follows below:

• Batman: Arkham Asylum (Eidos)
• Wii Sports Resort (Nintendo)
• Call of Duty 4: Modern Warfare (Activision Blizzard)
• Wii Fit (Nintendo)
• Ashes Cricket 2009 (Codemasters)
• IL2 Sturmovik: Birds of Prey (505 Games)
• Tiger Woods PGA Tour 10 (EA)
• Call of Duty: World at War (Activision Blizzard)
• Fight Night Round 4 (EA)
• Dissidia: Final Fantasy (Square Enix)

Source: Chart Track