There are quite a few real-world bugs still in NTFS-3G, I just saw one this morning from an Ubuntu user. While NTFS in its Windows implementations seems very stable, NTFS-3G has had less time to mature, so it's best to limit its use if possible - e.g. for a dual boot system put most of the shared data on FAT32 so that most NTFS writes are from Windows.
NTFS has advantages when Windows is running (e.g. it supports shadow copies for consistent backups of open files) but not for Linux.