Having flown and accumulated over 3 million miles on a half dozen domestic airlines, I can vouch for the value of elite status. As a Chairman's Preferred member in the USAIRWAYS Program,I HAVE NEVER FLOWN COACH in the past two years, even when using deeply discounted tickets. Delta's program is by far the worst and I've given up on them and haven't flown them this year. CO's program is excellent, except for upgrades on international flights. Obviously, I'm not looking forward to the US merger with UA and, quite frankly, hope it doesn't happen. US will survive without them if it doesn't happen and probably be an even better airline than it is today, although I have no complaints.
If elite status is within your grasps, GO FOR IT!