Although there is already a huge body of opinion here I jsut want to add my support to you to.
It never ceases to amaze me how much other people think they have a right to parts of your life. This is your baby, not theirs. Of course they will be excited about it and want to be part of their grandchild's life, but they don't have a right to muscle in on the precious early days that you have with your baby. They've done that with their own children, now it's your turn to have that special time with yours.
I can see that you don't want to upset people...I'm the same, I find it very hard to say no to visitors or even to invites to go out but it has to be done. I love my PIL, they are kind and considerate people that I get on with very well. However, DP and I have had to have to conversations about how being around them is still being "on duty" for me. Staying at their house is not being "on holiday" for me. Even the nicest DPs often don't understand this.
And if he has used your parents as an excuse for them not coming over:
a) so what ! it's up to him what he says to them and if they are a bit offended, it's less awful than having them come over to stay too soon and all falling out.
b) it's not unreasonable for you to want your own folks about, who you can be entirely comfortable with, but want to leave PiL till a little later.
Stick to your guns, you may have only been married a short time, but that's the time to establish that while you respect your PiL and want to fair to them, it is you, your baby and your new family with your DH that have to come first. The LO isn't going anywhere if they leave it a few weeks, and I love the webcam idea, maybe get a video camera and tape some early days and send it to them so they can show if off to friends and not feel like they are missing anything.