It had to be done, and boy am I glad I upgraded. I queued with many others at my local Apple store today. At 0800 the doors opened. Free Starbucks coffee and pastries were being served. I waited my turn and left with a boxed 16Gb White 3GS.
Later after work I swapped my SIM over and restored the phone from the previous phone backup. All my apps, contacts, etc. transfered without issue.
My initial impression; fantastic.