I wouldn't go so far as to say it's the only way to quit, but I do believe it's probably the easiest (relatively speaking, peeps, we all know how hard it is to quit ), studies have shown it's the most successful and it's certainly the least expensive way to quit. But when it comes down to it, any quit is a good quit no matter how you achieved it and I have a lot of respect for those folks who successfully kicked their nicotine habit using replacements because it's the more difficult route to take.
OTOH, I have three co-workers who have quit succesfully using the new laser accupuncture treatment; it's expensive; around $300.00 in my area and not covered by medical insurance, but it seems to be quite effective.
No matter which method is choosen, though, a quitter will have to go through nicotine withdrawal at some point; it's either that or stay addicted to nicotine through the replacements forever and keep paying the big $$ for your nicotine like your co-worker who is still puffing on that inhaler.