Sorry, I've been a little busy with work and writing up a Paleontology abstract (a small published summary of my research) and playing my SoulSilver version lately but I do want to talk about the features of the Pokéwalker. I've had one since I bought a Japanese version of Heartgold last year... but since I couldn't really read it I couldn't do a real write up for it.
First of all, if you aren't taking a stroll with your pokémon everyday.. you should. You would be surprised how much walking the normal person does in one day. The main draw is, of course, the ability to level up your pokémon. However, you can only raise you pokémon one level per stroll so that isn't that impressive as many people has hoped.
The other main purpose to use the PokéWalker is to use the Watts earned from walking to capture pokémon and find items. Early on, the pokémon and items aren't that great.. but the more you use the PokéWalker the more area you can stroll in. Some of the areas have really rare pokémon like Spiritomb and Torchic.
Although that is cool, I have found that one of the biggest draws for me to use the PokéWalker is to Mystery Gift with my friends for free items similar to in the old days of Gold and Silver. When two PokéWalkers sync, both people get a random free item as well as you can battle computer controlled versions of your friends team in Viridian City for Battle Points.
What do you like about the PokéWalker or do you think it's unimportant? Reply with your opinion!