As yet-to-be-released updates to the company's earlier cases for the iPhone 4 and other iPod/iPhone models, Speck's new CandyShell, Fitted, and PixelSkin cases for the fourth-generation iPod touch don't have many surprises to report. CandyShell ($35) continues to offer a classy, protective combination of rubber and glossy hard plastic, while Fitted ($30) has a textured fabric pattern on back with a less protective open-sided hard plastic frame,…