The colors on the banners probably match up to the colors that the Apple iPhone 5C will be available in. With a plastic shell and candy-coated look, this will be the budget model meant to take market share in emerging markets. The Apple iPhone 5S, like all of the "S" named iPhone models, will offer a minimal change in appearance necessary for the dual-flash and for the fingerprint scanner on the home button. Other changes, such as the faster, more powerful A7 processor, and the improved 8MP camera, are changes that the naked eye cannot see.
While the Apple iPhone 5C gets all those Skittle-ish shades, we also expect to see two new colors for the iPhone 5S with gold and graphite joining the traditional black and white.
Apple prepares for Tuesday's unveiling
source: iGen.fr (translated) via RedmondPie