Hmm... Lots of interesting views, and despite me finding this place while being annoyed that my stage preforming diplomat rogue with a spiked chain got squished by the no reach thing, and me being angry about it, I can't say I have a solid opinion one way or another. OR rather, a good solution...
The way I see it, this comes down to an argument about whether exotic weapons should be 'better' because you are expending a feat, or if you should expend a feat just to be different.
Personally, I think things that make you different but have no real 'usefulness' in combat or dice rolling shouldn't cost you a feat. Those things should be up to the DM and players imagination. For instance, I play a 3.5 campaign in which I have an elf Duskblade, which i chose because I thought the class would be unique and fun to play without being as useless as many other unique and fun classes. He worships Wee Jass as a few DBs do and i thought it would be fun to make him unusually tall, pale, and skeletal. He's 6 foot 9 and very pale, freakish for an elf. Maybe he has some Stone Giant in his ancestry somewhere. My DM didn't have a problem with this, and I consider him to be horribly against free thought. He didn't ask for me to spend a feat on tallness, or gauntness. it effects the game mech.s very little, I simply stick out in a crowd.
The problem with this is that when it comes to weapons, you wouldn't feel very special if your unique fighter with his exotic weapon ran into a brigade of goblins wielding the same weapon because it doesn't cost a feat. Exotic weapons should be rare.
But consider this. Someone said something along the lines of 'I pick up a sword, you pick up a chain, lets see who wins'... The logic there is -exactly- why exotic weapons should be better in some way to their martial counterparts. Yes exotic weapons are hard to use. It would take months, if not years, of training to get as good with a chain as you could get with a sword in a week. So why bother with the chain at all if it isn't any better? People spend a long time mastering odd weapons because those weapons give them an advantage in a fight.
I think that if a weapon isn't better, it shouldn't need a feat to be wielded. Making a player spend a feat (for many classes a very limited resource) to be creative is silly and directly against the point of pen and paper RPGs, which is to use your imagination, create a unique character, breath life into it, and have fun!
And if a weapon -isn't- mechanically different, then base it off something else. Like you a Samuri, (a fighter) who wields a Katana (a masterwork great-sword). Another option would be, hey, like the spiked chains 3.5 abilities but not the idea of one? Wield a Chinese long-spear, which are flexible and light enough to be finessed, and that same lightness allows them to be used close in by rapidly drawing the spear back or spinning it around to use the butt.
Note I'm not lobbying to get the old spiked chain back, (I've found a workable weapon in the Urumi) Just trying to shed some light on the issue and spreading around a few idea's for house rules. :)