Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
If Apple follows their previous history, the 5s will be released around the same time as Mavericks. Unless you need a new phone now due to hardware problems etc. I would wait.

Thanks!

I'll wait off, 4S is working great so far though battery time seems to degrade by the day
 
Apple is been on a yearly schedule, so I'd be very surprised if they skip this year.

Replace the battery yourself. Ifixit sells a complete kit I believe.
 
if you wanna save some money and buy a brand new iphone 5 off ebay, now it's time since the expected 5s might not be a big upgrade based on the experience from previous years. however, if you are going to buy one from apple directly, the price is still the same as when the iphone 5 firstly came out, maybe just wait.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.