Can anyone in the area help us out with new places that have opened up in the past while?   Always keen to try new places to eat!

If you are looking for something immediately downtown by the ICC, there is not really much that has opened up in the past year. Taxman Brewing is set to open up another taproom and restaurant by The Alexander Hotel, but looks like it will not be ready by GenCon. There are a couple places in Fountain Square or up Massachusetts Ave, which are >1 mile away but still within walking distance for most people if they're so inclined, but the majority of new restaurants that get news open up outside of downtown.

It seems like a lot of places have closed in the past year; certainly a little surprising if none of them are being replaced. 

I'd HIGHLY recommend Condado Taco.  It's a quick and easy build your own taco fix and some of the best tacos I've ever eaten!
 

Is that the new place out farther than the Rathskeller?

yeah it's about a block from where Rathskeller is on Mass Ave. Well worth the trip tho!
 

Bunch of new places too many to mention. Check the VisitIndy website. The new hotel across from the Fieldhouse has two that I know of. https://www.downtownindy.org/explore-downtown/eat-drink/
 

Not strictly new, but in the last few years my group has made it a point to lyft/uber out of downtown into surrounding areas.  

Kuma's Corner has great burgers.