To whom it may concern
The plugin (which is a very nice one) seems to have serious issues on latest wp and working on nginx + php-fpm. On every page load it causes php=fpm child processes to exit with signal 11 (SIGSEGV) thus making php not render the whole page, so blank pages. I have tested it extensively and every time i enabled the plugin my php-fpm processes started to seg fault. I disabled it for once and not using it again until someone fixes this issue.
Regards
Andy
http://wordpress.org/extend/plugins/upprev-nytimes-style-next-post-jquery-animated-fly-in-button/