• CCI Load Filter. CCI 2.1 adds a new component that acts as a gatekeeper to apps you designate as "disabled" in the CCI Preference Pane. With this in place, you can reliably turn CCI off for individual apps as needed, or disable CCI entirely using the Preference Pane button for that purpose.
• Background Blur Filter. Another major improvement is the use of a blur filter behind all windows, which is one more way to enhance focus on the frontmost window by minimizing background distractions. This blur filter is similar to the one Apple uses for its default sheet windows.
• Preset Themes. In the CCI Preferences window, you'll find a 5th tab called "Themes." I view this as a starting point for a more robust, extensible system of theming down the road (time permitting!) For me, the four themes included in CCI 2.1 are designed to complement the four desktop pictures I most commonly use, which by the way are included in the CCI download package. They are simply a fast shortcut for switching the frame style, transparency, and color of windows and text areas. Now, rather than having to do this each time I pick a different desktop picture (which is, I must admit, rather tedious), I can easily pick one of the four that works best.
• Matching Table Row Colors. Instead of seeing the same grey and white alternating row colors for tables all the time, CCI 2.1 dynamically sets the colors to match the color you've chosen for your outline views.
• Three new "Extra" options. In CCI 2.1, you can now
  • Opt to suppress the horizontal scroll bar in multicolumn file-browser views if you want,
  • Have the ability to move windows by any exposed background areas, not just by their titlebars.
  • Use the small scrollbar style for all your applications instead of the regular size.
• New Window Animations. CCI 2.1 uses a "fade-in" animation rather than the "move-in" animation used previously. I find this a bit smoother and less intrusive, and it causes less wear and tear on your windows by not leaving their screen positions in awkward places (like with their titlebars floating at the bottom with the dock) should you turn CCI off for some reason. In addition, I couldn't resist adding some new eye candy for windows as they close; now, the closing animation varies a little based on the kind of window that's closing.
• Modified Graphics. Some of the CCI system widgets have been redesigned... most noticeably, the titlebar buttons and the scrollbars.

• Clean HUD Windows. This has been on my to-do list for quite a while now, and I finally figured out how to do it right. In previous versions of CCI, the HUD window style that's applied to "utility" windows like inspectors, info panels, and utilities like the font and color panels didn't display the smooth rounded corners at the top and bottom edges that you expect from those Apple includes. Instead, you'd see a faint horizontal highlight artifact at the top, and the bottom edges would be squared off. Now, that design flaw is gone, and all CCI HUD windows look the way they should have all along. The screenshots below show the "before" and "after" views.
• Support for "Garbage Collection."A growing number of Mac applications utilize the "garbage collection" feature of Objective-C Apple introduced in Mac OS X 10.5 ("Leopard"). This version of CCI can be used by these apps, which include Xcode, Smultron, and others.
• Myriad of Smaller Enhancements. One example is that the CCI Help window is now resizable, so it should be somewhat easier to read.

More information, including screenshots and documentation, is available on the CrystalClear Interface website.