It is intended.  I don't think it's very fun to lose your progress on a wonder because someone else in the world finished it first.  It's not a bad mechanic in the right game (I tend to think there aren't bad mechanics, just mechanics that are bad for a specific game) but with all of our focus on the unit side of the game adding a management task on the city side doesn't seem great.

I also worry that when players get beat to a building by the AI they would reload their autosave and rush it, so it would be particuarlly bad for the AI.  But I could live with that if I thought it was fun.

AI's should understand this rule and have a shot at queueing up a wonder when they get the appropiate tech.

Maybe starting a wonder should have an extra cost to discourage this- or have a fame cost to build wonders.

If it is the exploit that people are worried about, maybe it should be the case that for world wonders you cannot change it's position in the que... You can cancel it's construction or you have to build it until it's done... but you cannot que it up for later construction, something that needs your sovereigns direction to build.

Or I think that limited world items (like world wonders) should not be able to move later in a que... once qued up they can only be moved forward in the que not backward.

But on the fun list here, not sure if it qualifies as fun...but it might make other players feel less cheated, knowing the AI has to build the wonder and if you attack the city building the wonder the AI then has to make a choice to stop construction completely and rush a defense unit or risk the fall of the city. Puts a whole new twist on how to stop somebody from building a wonder.

Basicaly consider yourself as a winer in building race if you got that tech first.

I think its new aproach and i like it. We were so fit to old CIV or similar game ideas about wonders, so we probably couldnt accept it with ease now, but i think Derek ir right at this point, You racing not at building process, but at posibility to start it. After all wonders are great by idea to build it mostly. You first have to have an idea to build it and only then you can proceed with building.

I dont think you need a message. If you got tech for wonder and met all requirements and still have no building on meniu, then its clear conclussion - someone already started it.

Another solution would be to add the qualifier: world wonders can ONLY be selected for building IF they are the only item in the queue.

Naturally, one would also have to add: When a world wonder is in the queue, no other item can be placed in the queue.

If this were intrroduced, than I would be fine with Derek Paxton's justification of the matter. Without the above qualifiers however, it's just one massive exploit...

I really like the idea of announcing when a player starts to build a wonder, so I don't make that tech such a high priority. I just jumped from one tech to the next trying to get a wonder, and both times I was blocked. That lies squarely on the frustration side of the Fun scale.

Parrot's suggestion of being unable to move World Wonders around the que is great. I'd like to take it a step further and say there can be nothing in the que at all when you start building it, to prevent players from queing up lots of unit and structures right before they select the World Wonder.