The great offer of viewers, alternative to the official Linden Labs vesion, makes difficult for users to make a choice. This article will try to spot the differences between them and how they're going to evolve in the next future.
A quick recap first.. Once upon a time there was viewer 1.0. It was the only access door to Second Life, and in many cases it revealed itself as an obstacle to those willing to approach the most popular virtual world in the net, because of the long time needed to learn how to use it.
This viewer has been designed in a time people wasn't much aware of the great role interface design could play in a user experience. Focus was mainly on features users were supposed to need. At some point, Linden Labs started
Snowglobe project, to allow the development of custom viewers, and people felt encouraged to improve it, adding more and more useful features that helped greatly in improving usability and user experience.
Inside this context many third party viewers were born, and among all Emerald Viewer, an alternative choice that many Second Life users adopted gladly, featuring a radar, a sim scanner, bouncing boobies, rlv and many interface improvements, like vertical chat tabs.