It wasn't too long ago that I first tried the Nike+ iPod combination. Then in March last year I bought iPod Touch to work with Nike+. I should have waited few more months because Nike+ App was built into iPhone 3GS launched last June. All along heart rate monitoring has been missing from the Nike+ running gears.
In April Adidas overtook Nike+ by introducing miCoach, I tried that immediately. There are similarity between the products such as (1) put it on (2) run (3) upload your data to their site. miCoach offers vocal coaching while you run and in my opinion their website looks/works better. The difference is a gadget clipped onto my shirt.
To compete 'time to market' is the key so instead of developing something on their own Nike+ decided to work with Polar, here it is below, available now in the US for $70. Currently only 5th Gen iPod nano supports this I'm sure when iOS 4.0 rolls out end of June the updated Nike+ App will be able to pair with this.
Will I try this, don't know yet, I'll see what vocal narration is available and how Nike+'s website will look like by then. It'll be attractive to me because I don't need that gadget (not waterproof, can't run in rain) clipped on my shirt and in the middle of the cable between my iPhone and the earphone. I can't run without a phone, music, additional gadget seems unnecessary unless it's really useful in tracking my workouts.