It's more regular than evolved languages, easier to learn, and based on vocabulary taken from several European languages. It has probably a million or so speakers, and there are even a few native speakers. See also Don Harlow's Esperanto site in North America, and Martin Weichert's Virtuala Esperanto-Biblioteko in Sweden. Glosa Intented for international communication. What inflections it does have are marked with dashes so they're easy to pick out.
Some critics say it's just a code for English.
There are a few more articles about it here , some of which are in Esperanto. InterScandinavia A merging of Scandinavian languages. A version of Interlingua. Novial A proposed international language, invented by Otto Jesperson. Bruce Gilson put it on the web as an example of something he likes better than Esperanto.