Well, I'm a three-day-old convert from Windows and let's just say it's been a rocky start. My brand new PB 15" 1.25 G4 (Panther) froze and remained frozen upon inserting the first disc (brand new), about an hour after turning it on for the first time. After restarting I was able to extract the disc and I haven't had the same problem since. However, later that evening, when I restarted the PB after calibrating the battery it froze again (after the clock reset to 12/31/1969, which it does every time the battery runs down). Like the first time, no keys were responsive, the pointer frozen. Despite multiple reboots nothing worked. It remained frozen the whole weekend. And then, for no apparent reason, on reboot 17 or so it just started working. In my half-day of use since it's been great. But... I'm obviously paranoid now that I have a lemon. The apple care guy dismissed it as "a system anomaly," and said "I may never see that problem again." And naturally, since it was then working, an exchange was out of the question. Obviously, for the $3,000 I spent and all the marketing and popular hype I believed in, I'm significantly disapointed. The real question is: How do I know my OS is up to par? Should I push for an exchange? Can anyone ease my concerns? Validate them? Thanks!