Just wanted to chime in, having just spent my birthday at WDW last week.
Stayed at CSR (not that it matters)...I thought I had noted my bday on the resort reservation, but the CM said nothing...everything at check-in was matter of fact. (She didn't even notice the date on my i.d. when I presented it at checkin...no big deal...I wasn't about to make a big deal of it.)
So...we got our standard room, just as reserved. And it was just fine.
I did get a bday button at Guest Services when we went to MK that evening before my dinner at CRT. I got so many "Happy Birthday" wishes from CMs and characters...and since this was my birthday treat, I was genuinely tickled with each one. Nothing else special that day or the next...I figured I could go ahead and wear the bday button for each park. We did the Tusker House character breakfast on our 2nd full day and that waitress CM did bring me a cupcake and bday card. So cute!
But other than lots of "happy birthdays" that was the extent of it. And I was happy with that. If I had wanted extra cakes or whatever, I could have ordered them. I felt no need...just being there with my own Prince Charming was enough.
So, my suggestion, like many others will tell you here. Expect nothing extra. Then, if you get a little pixie dust, it's a bonus.
