Nikon has announced the new SB-910, a top-of-the-line flash unit to succeed the SB-900. Instead of increased power — the guide number and zoom range haven’t changed — Nikon has chosen to focus on usability. The new flash features a new MENU button and improved LCD user interface that are designed to make operating it a breeze. It also automatically detects spiking temperatures, and slows down the recycle rate to automatically prevent overheating. The price fits the SB-910′s place in the Speedlite lineup: it’ll cost a cool $550 when it starts shipping on December 15 — more than some entry level DSLRs.