Alex, the creator of the best image gallery plugin for WordPress i.e. NextGEN Gallery has decided that he’ll not make the version 1.0 backward compatible with other older versions of WordPress. He insists that if people don’t decide to upgrade to WordPress 2.7 then they shouldn’t upgrade the plugin too!
Apart from that it makes sense that one should upgrade WordPress ASAP because it helps you in keeping the security breach’s away and makes your blog more secure.
