You definitely have to pick a new number. And, if you're a vanity number person, be prepared to pay a lot more. The good news is that you'll still have around 5000 (WAG) numbers to choose from. Plus, after I made the switch (new business cards and all other related annoyances), my monthly spend dropped from y600 to y300 (this is more than y140 because of the roaming and long distance charges). The main advantages to postpaid are: 1) cheaper; 2) you never need to worry about shopping for recharge cards --that may or may not work-- at 1a in strange cities.... or bothering friends in your home city; and 3) you can make local calls guilt free as long as they fall within the parameters of your rate plan.

Regarding #3, before I made the switch, I used to look up numbers in my cell phone and key them into my home or office phone, simply because I felt cell phone calls were excessively expensive (let's set aside the fact that their cost relative to other daily expenses is trivial). Now, I take full advantage of my cell phone's functionality without thinking twice. And, I only give out my home number to a select group of people so that when it rings, I have a pretty good idea about who's calling (I don't have caller ID at home).

In short, I encourage you to spend an hour (maybe only 30 minutes, but allow for an hour) at your local China Mobile office and get onboard. Unlike in the US or Europe, you won't be locked in to a burdensome contract (unless you take one of their "free" phones in the process); whenever you leave China for extended periods of time, you can simply drop to a y5 plan that will preserve your service or cancel altogether.