People have pretty much covered it but here is what I believe is essential in a Delphi for Game Developers Edition:

Crossplatform compiler (x86, x64, ARM...) (Windows, Mac, Linux, Android, IOS, Windows Phone...) - Must be easy to target any platform without any (major) changes in code.
Solid list of libraries - You know one of the big reason I like Oxygene for Java? I get the entire JDK library and can find pretty much anything on the internet. I don't expect Delphi to compete with Oracle on the size of the default library, but any data container, file reader/writer, stream system etc. must be included in a preferable memory efficient and high performance version.
Game/Media specific libraries - I don't expect Delphi to be included with all the game frameworks/engines out there, but as everyone else is saying: "At least get up to date headers for OGL, DirectX, OAL...".
IDE - a really good editor must be included. Visual editor would be nice for tools programming, but the code editor must be great. Anything that can be automated should be (with possibillity to turn off) to improve code production. A great debugger with memory inspection etc. is also needed.
Profiling tool - If you want to be serious about your games this is a requirement. You need to be able to inspect your memory usage and find bottlenecks, so you know where to optimize your code and where you can add a bit of extra wow to your game.
Cheap - and no stupid licensing requring you to pay additional fees if you actually make money.

I'll admit it's been a few years since I last actually followed and used Delphi. I went with FPC since it was just as good for my needs (if not better) and a lot cheaper. After receiving a free license for Oxygene for Java I've been using that and plan on continuing to use that paying for an upgrade when I need it.
However I have a hard time seeing Delphi regaining customers who have switched to FPC/Lazarus. Delphi's force is database applications and that kind of things. They do it well and their prices may be fair for that kind of usage. However it's mostly useless for indie game devs. Yes there will be times when databases are needed for games, but for most people this isn't a must.
If you strip away the things we don't need from Delphi it doesn't really compete well with FPC. Yes Delphi will be crossplatform eventually, but they will need to do it so much better than FPC or Oxygene and offer a lot more, if they want to sell me a copy of Delphi versus downloading FPC for free.

IMO Delphi is just not for game developers. Sure if you need Delphi for anything else then you can use it for Game development as well. If you just want to make games in Pascal; FPC is fine, and if you're not set on using Pascal there are plenty of other free solutions out there. I'll always have a soft spot for Delphi. It was the first programming tool/language I ever used but I feel like we've grown apart and a reunion is not likely.