"In terms of usability, the slippy map increased the affordability of the map with direct manipulation functionality for panning, clear zoom operating through predefined scales, the use of as much screen assets for the map as possible, and the iconic and simple search box at the top. Though the search wasn’t perfect (see the post about the British Museum test), overall it offered a huge improvement in usability. It is not surprising that it became the most popular web mapping site and the principles of the slippy map are the de facto standard for web mapping interaction. "He then goes on to note a pet hate about street view:
"However, in recent months I couldn’t avoid noticing that the quality of the interface has deteriorated. In an effort to cram more and more functionality (such as the visualisation of the terrain, pictures, or StreetView), ease of use has been scarificed. For example, StreetView uses the icon of a person on top of the zoom scale, which the user is supposed to drag and drop on the map. It is the only such object on the interface, and appears on the zoom scale regardless of whether it is relevant or available. When you see the whole of the UK for example, you are surely not interested in StreetView, and if you are zooming to a place that wasn’t surveyed, the icon greys out after a while. There is some blue tinge to indicate where there is some coverage, but the whole interaction with it is very confusing. It’s not difficult to learn, though."
I see what he's driving at but I don't really share his dislike of this feature. Sure, its an oddity but its immediately obvious how to work the functionality. I'm also happy with seeing it at all scales - sometimes I want a high level view of where streetview is available to know if I can use it in an area. On the topic of too much functionality I also wonder if the public now is so used to the basic controls (zoom, pan, slippy map, search) that it isn't much of an issue adding more functionality? Of course, it does add to screen clutter. One feature of GMaps I really don't like is the little circle above peg mans head. What does that do? Why is it there?
Muki then goes on to discuss Google Earth interface:
"There are similar issues with Google Earth – compare versions 4 and 5 in terms of ease of use for novice users, and my guess is that most of them will find 4 easier to use. The navigation both above the surface and at surface level is anything but intuitive in version 5. While in version 4 it was clear how to tilt the map, this is not the case in 5."Here I totally agree with him. The controls in GE5 are complex and behave in odd ways. I bypass them completely when teaching about GEarth and teach people the mouse controls (Click and drag to pan, click mouse wheel and drag to rotate around a location and alter tilt, roll mouse wheel to zoom in and out). GE4 controls were much better.
On a related topic, I've talked about the usability of the layers panel in GE before
I share Muki's wish that Google don't lose sight of the value of simplicity, functionality is good but a complex interface can be unusable.