Still Lovin' the Whole Idea of a Quilt Guest Book

Image from Style Me Pretty

Oh happy, delightful day! Remember a few weeks back I posted on a Guest Book Quilt. Well guess what ladies. I found a real wedding that has done it! (I think)

Basically guests write their well wishes on a square of fabric and hang them to a line with a clothes pin. I especially like this idea because it appeals to my social media sensibilities. Guests can see each other's comments. Almost like a comment thread on a blog {grin}.

Images from Style Me Pretty

My only question is: what kind on pen did they use? I am thinking I would use a permanent, archival quality pen. But would it be better to use a fabric pen?