We're getting there to that best-for-now world of having both wi-fi and cellular access. You get the faster speed of wi-fi when it's available and fill in the gaps with the slower but more pervasive coverage of cellular. This Sony-Ericsson GC79 GPRS/wi-fi PC card rocks!
It's announced now. Where it's available, I don't know. I would much rather have one of these in my Powerbook than a simple wi-fi card. But, as usual, cost is an issue. I'm paying T-Mobile $20 for unlimited data access with my cell phone now. Plus I'm paying $20/month for T-Mobile wi-fi access at Starbucks et al. Seems like I'm paying enough already to T-Mobile. T-Mobile should be nice this time - no extra charges please? Probably, wishful thinking...