Hmm I followed the directions on the package that said Mid may to early June, and an article from a local newspaper said:
"Early to mid June is about right if you�re going to plant seeds directly into the ground."

I thought I was planting early in hopes of giving them a head start.. If I wont see pumpkins until the vines are 8-10 feet long then I better start hoping the great pumpkin comes blesses my garden lol.
I have no vines they are just sprouts popping up from the dirt about 4 inches...
Ah well maybe next year I will have better luck...

So does anyone know what size they SHOULD be about this time?

That is a very hard thing to say due to local climate conditions varying between everyone. Where are you located? What has your weather been like?

Mine are just now reaching the point of producing female blossoms.

Typically I would say early to mid may is a good planting time depending on locale.

Also how often are you watering them and how were they fertilized? They do like to grow in spurts so they may take off this month.

Region 7 Washington state. Our weather has been wacky! We are having a very cool summer it has only got above 80 a couple of days & there has been a lot of cloudy days. I water them in the morning & at night. Before the sun hits the garden & after the suns off of it.
I guess I will just hope for the best. I will be happy if I get one even its a mini pumpkin. :o)

based on your climate which is like mine but colder, you should have a vine between 10 and 30 feet with some or many offshoots. My vine is absolutely gargantuine and yet still hasn't developed any successful pumpkins. 2 did get pollinated, but they were aborted. Right now I have my hopes set on one more that got pollinated. Beleive me, my first few pumpkin trials were worse than yours. They need lots of water especially in a climate where it doesn't rain much in the summer, which I beleive you have (right?). Also, the soil could just be wrong. Try making a mound of compost, which you can buy bags of at the garden center, and then plant the seed in there once its 60 degrees outside, or start it in a window sill and then plant it outside when it's about 60 degrees. Never let the soil get very dry. When you stick your finger into the soil a few inches it should be damp to soggy. NEVER plant the seeds directly in clay soil, or some non-compostish soil. This is just a death wish. For some reason pumpkins only grow in my experience when they are planted in compost or compost based soil. I'm in California.

good luck next year

sitting, you should try an experiment and cover the baby pumpkin with a light colored towel to shade it from the sun. after you pollinate it.

I didn't even notice your location in the original post. shame on me.. Our weather has been pretty wacky this year but my pumpkins are probably 10 feet or so (although I'm wrapping mine up a trellis so hard to say).

As far as the 60 degrees thing goes, we didn't consistently get to 60 degrees until well into June. I risked it and planted mine in may and I just starting seeing my first open female blossoms yesterday. Now to get male blossoms and female at the same time.