Most of the people are doing it in blue fingering weight. No surprise there as it's what the pattern calls for. I didn't find anyone using the same yarn as I am. There are a few using the original's yarn from Lorna's Laces. A number of people are using different kinds from Knit Picks. The only one I was a little jealous of was a blue with sparkly stuff in it.
There were a few choices that baffled me. Multicolored yarns? I wouldn't want to do that much work and then not even be able to see the pattern. I'm not talking shaded, I'm talking colors with extreme contrast between each of the colors. My yarn's shaded and I'm hoping it'll be okay. Laceweight? Unless you're making it for a tiny person, I wouldn't think that would work. You'd have to use big needles to get gauge and the Tardis pattern again might be lost. Bulky yarn? I can't begin to guess what that person was thinking.
I think I'll go take a look at the pattern again. There's a section where you have to pick up 300 stitches and I'm quite sure I'm going to want to find another way of handling that little chore.