I've been looking at both of them as well. The difference is, with the Micro,
http://reviews.cnet.com/Creative_Zen_Micro_5GB_black/4505-6490_7-31151919.html
you get style points, as well as a removable battery, FM Tuner and Voice Recording features, which are not standard on the larger-capacity Zen Touch.
http://reviews.cnet.com/Creative_Zen_Touch_20GB/4505-6490_7-30907933.html
Good luck
These players are the same price on Creative's website. I can find the Micro for $30 less on Amazon, but they are relatively the same price. I'm in the market for an mp3 player and I don't know if I want an iPod. I'm thinking about the two Zen players, if they are the same price, why would I get the Micro? Thinking the Touch holds 20gb. Any sites that kind of compare the two?

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