I agree with everyone else, as mother of the groom you should be elegant and classic, willing to take a back seat to the bride, bridal party, AND mother of the bride. It's not about you.
Since I had my boys in my 30's, I guess I'm glad I'll be mother of the grooms. In your post, I would be the "older" woman you're trying to show up and it would be very hard to feel happy about merging two families under those circumstances. I'm happy you are taking advice in stride, because I think you should try really hard not to alienate your son's new wife and his mother by trying to make a strong statement (especially if that statement is that you're not old like her mother) at the wedding. OUCH!
I also feel strongly that if the MoB is not changing dresses, you shouldn't.
Since I had my boys in my 30's, I guess I'm glad I'll be mother of the grooms. In your post, I would be the "older" woman you're trying to show up and it would be very hard to feel happy about merging two families under those circumstances. I'm happy you are taking advice in stride, because I think you should try really hard not to alienate your son's new wife and his mother by trying to make a strong statement (especially if that statement is that you're not old like her mother) at the wedding. OUCH!
I also feel strongly that if the MoB is not changing dresses, you shouldn't.