Well, think back (not that far).
Rumor for 2013 was: announce in June, ship in July.
Then, rumor was: big delay on all products.
Maybe second rumor was a smokescreen, and we're back on for June/July?
But a change in screen size for the 5S?
History would suggest not: 3G/3GS, 4/4S
(any chance a change in screen technology? maybe)
No change in case size, nor battery size, though.
I'm just reading the tea leaves.
Probably see new BIGger, brighter, & lower power display in the iPhone 6.
Would Apple dare bring that out for Christmas if the 5S came out in July?
Seems a bad idea from a PR standpoint, but they did shorten the life of the iPad 3 by rushing out the iPad 4.
I wouldn't place a bet either way.