There are a lot of new TLDs (top level domains) available nowadays. You could register your domain in the old school ".com", or you could register under ".gallery" if you perhaps ran an art gallery, as just one of many possible examples.
But I wouldn't. I'd just stick with good old dot com. And here's why.
- Different, new, possibly lightly used TLDs have a risk of being perceived as spammy. Which ones are believed to be spammy and which ones aren't, I'm not able to tell you. That research is something I just have not done myself. But look at the historical precedent with the .biz TLD. Or how about .PW? Yeah, those aren't very recent examples, and newer TLDs could perhaps be better policed or have a better reputation. But it's not something that I'm not going to risk or even bother with, and I don't think you should either. Some spam filters may be suspicious of your unusual TLD choice. Maybe not many, but why risk it?
- If you use a domain name with a long TLD (like .photography, for example, you could run into email systems that won't recognize email addresses at your domain. Some older internet systems may be hardcoded to allow only the very old school list of TLDs that the internet was locked in to for oh so many years. Also, some of them might only allow for a 3-4 letter long TLDs, depending on how they're coded. Is this problem that common? No, but, it's something I've personally run into when testing email over new TLDs.
- I don't know anything about ".net" but what I've heard of people having trouble with ".org" domain suspensions. I don't quite understand the reasons why, and I'm not sure if it relates to this complaint about .org policies from the Electronic Frontier Foundation, but it's not something I'm really eager to learn more about the hard way.
- I think we still have a long way to go before most of the general public understands that the internet is comprised of many more TLDs beyond .com. For better or worse, sticking to what everyone already knows might make it easier for your random less-savvy internet user to be understand or reference your email domain name.