Community Manager & Harbinger of Soon
Yes there is a filter. However, as we remind everyone, regardless of whether or not there is a filter our rules specifically prohibit the use of profanity. That means if you type it and send it, you have violated our policies and may be subject to consequences.
Fortunately, we don't see many issues with profanity or people using it very often.
Rick Heaton, Community Manager, The Lord of the Rings Online.