Bad CF card or camera problems?

I just purchased a PNY 2GB 266X Compact Flash card, and noticed that every now and then I get shots that get some weird noise in the very same spot:

And another shot on a different day, same card:

Both photos were taken with my Tamron 90mm lens. Has anybody experienced this problem? Card problem, camera problem, lens problem?

It's usually the last photo of a batch.

Mine's bigger than yours: My wife's MacBook Pro vs. my MacBook

Benchmark Results

Bottomline Geekbench Scores: 

MB 3208, MBP: 2656

I downloaded Geekbench 2.1.2 and ran it on both Macs to compare the scores. The chart above was created using Excel.

TECH SPECS

1) MacBook Pro (17-inch)

• OS: OS X 10.5.6
• CPU: Genuine Intel T2600 (Core Duo) 2.16 GHz
• Cores: 2
• Bus Frequency: 664 MHz
• L1 Instruction Cache: 32.0KB
• L1 Data Cache: 32.0 KB
• L2 Cache: 2.00 MB
• Memory: 2.00 GB
• Memory Type: 667 MHz DDR2 SDRAM

2. MacBook (Late 2008)

• OS: OS X 10.5.6
• CPU: Intel Core2 Duo P8600 2.4 GHz
• Cores: 2
• Bus Frequency: 1.06 GHz
• L1 Instruction Cache: 32.0KB
• L1 Data Cache: 32.0 KB
• L2 Cache: 3.00 MB
• Memory: 4.00 GB
• Memory Type: 1067 MHz DDR3 SDRAM