On your "my page" you do not list your zone or location. This would be helpful.
If you have had temperatures that are low, toward 40 degrees, many young herb and vegatable plants cease photosynthesis and don't produce green chlorphyll, exposing the other colors in the plant. Has it been very cool since planting? That may be the problem. Only a guess.
hortster

My (regular) oregano turned completely purple over the winter. It's been warmer for a few weeks now and it's turning back to green. I've been using it normally, with no apparent ill effects to the plant, recipes, or me.
I'll take hortster's word on the explanation; purple pigment seems common in the mint family (see: purple basil, purple deadnettle, etc), and the temperatures seem about right.

Hi, Hortster and Lalibellule! Thank you so much. It sounds like the cool weather we have in the evenings is indeed the cause. The thyme stems are still purple and a few more of the Greek Oregano leaves but hopefully this will all turn back to green once the weather is warmer again! Thank you. :-)

I once had arugula pick up some color from the plastic pot I had it in......

Gardenathome it looks like you are in zone 9/10? Why aren't they in the soil? The do great here and north

Thyme plants are native to the Mediterranean and is considered to be hardy in zones 3 - 7. It is prone to disease and insect infestation in the deep south and we usually don't recommend it to our southern gardening friends.