UPDATE:
We had the formal nights on day 2 and 6 (8 day cruise). I wore the same dress, but I had brought a different one "just in case". The other days had themes, but not the ones that shoreside had mentioned and it was only the servers who dressed up for them. We were pretty casual on the other nights. While I tried to wear something nicer each night, my boys, and DH were all in shorts and t-shirts on the non-formal nights. To their credit, though, none of them complained about putting one their suits or standing for photos when I asked.
Because Starvenger asked if I bought the photos, here was our result and experience.
We ended up having 60 photos to choose from. Some were so close to the others that it wasn't too hard to choose 50 out of the 60. I would have liked a few more dining photos, at least on formal night, but they were only around once and it was a casual night for us.
We managed to get to the photo spots early, so we didn't have to stand in line, but I saw quite a few long lines later on.
One thing, the iFly photos that were taken of my kids were not included in the package. That surprised me, as it was an event on the ship, but I guess maybe it's run by someone else. Not sure. Anyway, there is a separate pricing for those photos. You can buy a print (or 3 or 5) in a folio or you can buy a digital download of 30 for $99.99 or all for $149.99. Well, my kids only went once so there were only 10 photos and actually only 4 of one and 6 of the other.
Anyway, I'm a sucker for photos of my kids (even though they're adults, lol), so I bought the downloads. I had hoped they'd throw in the extra 10 photos from my other package, considering I was only getting 10 of the 30 iFly photos, but not deal. Even though they show up in your room the same way, they are not the same package. In fact, I had to select the iFly photos and download them to my phone before I could finalize my 50, or they would double up in to my 50 count (even though I' already paid for them separately). I had to get help to get it completed, as they had to remove the iFly photos from my account once I'd downloaded them.
I got my download email as we were leaving the ship. Everything worked fine.
TIP: Don't wait until the last day to start choosing your favourites and finalizing your downloads. It has to be done at the Focus office (5th floor of the Odyssey) and it gets busy as the cruise winds down. I remember
DCL being the same way, but at least, on DCL I was able to buy the package of all the photos, so I didn't take up a screen or time choosing which I would be selecting. Royal doesn't have an "everything" package, so you have to select and finalize your downloads. Once done, you can't change, so everyone waits until the last day to do it.