I've done it in several ways, so allow me to share a few possibilities!
The first couple times, I simply made a collage-type scrapbook page using the photos from some of the photo cards we received—not all, I don't think, though it's probably most of them, since photo cards weren't quite as common in the mid-oughts as they are now :0)
Another approach is to build a pocket into the scrapbook page. Our card and a headline are front and center, but a pasted-in pocket (an actual envelope, in one case) holds all the other photo cards, accessible through the top of the page protector.
Last year, I made the pockets for all and for ours out of the same page protector, running it through the sewing machine to seal off our card at the bottom and doing the tie-closure again at the top. The downside of that design is that only one friend/family card is very visible on the front and one on the back, because the pocket is so small. Typically, I like to flare the cards out some, with favorites near the top so I can see several even without opening the pocket.
This year, I was less crafty about it and just purchased a pack of Project Life envelope pages. I added a little embellishment at the top, but otherwise let the nice plastic envelope do its job. It has a nice 4x6 pocket on the front for a journaling card to explain the envelope's contents, but I left it empty to let the cards inside speak for themselves. (And I look forward to using the other two envelopes in the pack for Kate's schoolwork and other big items to save!)
I made a simple cut-down page protector for our own card.
I love looking back at our own family's cards through the years, and last year I crafted a decoration to let me and any guests to our home see the progression of our family through those cards, from our marriage to pregnancy, one child to two, and so on. Burlap, a wide sparkly ribbon, and a bunch of paper clips with scraps of ribbon on each one were all it took.
I hope these ideas prompt you to get creative in saving those photo cards from family and friends, and in the words of our card this year, we are WISHING YOU PEACE, LOVE, AND JOY this season and always.