Perentage system $$ for speakers

While reading various posts in the past, I have read comments where some believe that the speakers should only be about 15% of the total system cost where other believe they should be the main focus. I am not looking for a right or wrong answer in this, I am just curious as to the thoughts of others on this topic.
My experience is not the same as yours, Mailman. When I auditioned speakers, there was a much more immediate and noticeable improvement in those over the lesser models and my old ones than by switching electronics. As a result, right now, I probably have about 50% in the speakers. That said, I am now upgrading the electronics, and will probably end up in the 30% range when done. If you're willing to buy used, amps and speakers are generally avilable at about 50% of list, and last forever ... but sources (espec TT) may be more prudent to buy new. That would certainly drive down the % that the speakers represent.
I think that your speakers and amp should be considered as a single purchase for pure synergy. That combination will run 50-60% of total system budget. In my case the retail on my speakers is $15,000 and the amp is $10,000 and my system total value is about $50,000. These numbers seem to be about right in my case. I mention the amp and speakers together because it is so important to get the part right to get the most out of your speakers. Garbage in - garbage out. Every speaker designer has voiced their speakers using some type of amp and if you find out what works best the speakers will sound their best.
I think that it really doesn't make sense to reduce the purchase of speakers to some formula. We all know that paying a little or a lot for speakers is absolutely no guarantee of quality or that you wil ultimately be happy with the purchase. I would say that you want to get the speakers which please you the most and which match the equipment you already have while still allowing you to stay within your budget. That said, this is still a very difficult task in practice, but why make it even more difficult? If your total audio budget were say $50,000, would that say that you have to buy a speaker for $15,000 $20,000 or $25,000? Why? Especially if you can find a speaker for $4000 that sounds as good or better? I agree with Eldragon that while speakers are very important, pay close attention to the preamp. That is where in many systems good sound is turned into bad. I personally don't like the idea of spending megabucks on speakers since at any price point, these are the most "flawed". And raising the price point doesn't necessariyly get you a less flawed product.
By the way, all those crazy audio allocation formulas are forwarded by those who want to take your money and therefore the formulas don't benefit YOU! These include the manufacturers, the store sales people and the magazine reviewers who all benefit by getting you to buy the most expensive, rather than the best equipment possible. It just doesn't follow that because you spent or intend to spend X number of dollars on your entire system, that some percentage of it should be spent on any particular piece of the system. As you get to know the available equipment and what works well with what, you will know on what product you need to sacrifice cost and on what product you can make up the cost overrun.