Until recently, the only way to fix MacFUSE's incompatibility with Lion was to install Xcode and Macports and compiling a bunch of code. None of that is necessary anymore. To get NTFS file systems into read/write mode I recommend removing the old MacFUSE (only if you used it before upgrading to Lion). If the uninstall button in the preferences panel doesn't work, control click on the preferences panel icon and select remove. Reboot your machine.