It seems that ezinearticles have become quite strict in accepting articles lately. One reason could be that for some time now the articles posted at ezinearticles were not coming up that high in search results. In fact sometimes the articles submitted to other article directories shot up to a higher result than articles submitted to ezinearticles. However, the eza people seem to have woken up to the fact and now are very strict about the quality of articles before accepting them
Always, always provide value with everything you do. Make your article information rich and keyword focused for the best results. -Ryan