I don't like it. You said one reason you do like it is that it mirrors the welcome message on the s.b.e start page, but I think that actually argues the other way! The user has already been welcomed on s.b.e, and it's redundant to welcome them again, especially since it keeps welcoming them every time they finish reading a thread. If you saw the banner only the first time you land on the landing page, it'd be terrific.
Bh doesn't want user to be welcomed 
/j
When I select "Latest", "New", "Unread", the banner is still there...
Perhaps it's a cultural difference, but this form of automatic kindness feels rather artificial and pointless.
I agree with both dardoro and bh. If someone kept telling you "Welcome back!", then it would feel less and less natural. bh's ideas would work great.
The homepage has said 'Welcome' for like 8 years... the welcome message there is on the home page no matter how many times you visit it.
Though, I suppose if folks "just use bookmarks" then you don't see it there... I don't know. I do not think there's a theoretical basis for when you should/shouldn't see a 3 word welcome message. But perhaps folks should post on the actual discourse forums. Or if people really want, you could maintain a plugin I could enable on one theme. (Though, I am reluctant about breaking the forums, given that I spent almost 20 hours in total over the last week trying to fix things..)
But, still, there should be a more prominent search field and the design w/o the welcome message was differently criticized so, I'm not sure everyone will be happy...
Personally I like the welcoming message, the theme and the search bar on top of the page. You can not make everybody happy. As long as you are happy since you have to maintain the theme. 
I noticed the font has changed too... Can I please have some insight on that, as well as what font you used? Thanks!
The forum homepage? Interesting. Maybe it's just gotten bigger? I don't mind the message itself; what I mind is that I can only see two posts listed below it and the search bar.
In a perfect world, we'd be able to make everyone happy about the search bar by putting it up in the header, next to the existing magnifying glass icon, so it would be prominent without taking up precious vertical space.
Yes, I see the irony that I argue with Jens about his vertical space fetishism in the palette but I'm fetishizing vertical space in the forum. But I claim there's a qualitative difference between the two forum posts I see in my forum window and the 18 blocks I see in the palette.
The community site homepage. The difference is that the "Welcome" header on the forum page is huge, and you'll spend the majority of your time on the forum not reading a post on the homepage.
Whereas on the community site, you'll spend the majority of the time not in the editor literally anywhere else than the homepage.
on my screen it doesn't seem to take up too much space..?
maybe it is because of display scaling. Since i have a huge monitor, the welcome screen takes up less space.
i just tried every theme and i cannot get it to look like this.
Here's my proposal:
You store whether the user has seen the header in session storage. If they have, it won't be there on the next visit. When the user closes out of the browser and inevitably comes back to the forum, the session storage would have been reset, and the header will show.
Yeah the problem isn't that it's hard to design a better way; it's that this isn't the work that Michael is paid to do, and he's really swamped. And he's just coming up for air after what was supposed to be a routine reboot turned out to cause unexpected problems.
(Yeah I know, this applies to my suggestions also.)
The problem with that is, that would take a while to write a plugin for, since michael can't just easily modify discourse to do whatever he wants. You should suggest it on meta.discourse.org.
The body font is supposed to be Inter, I think, but tbh, I am not seeing any change...which is weird.
I can play with this later, but I think Discourse's implementation of the navbar is kind of ugly. But there is a setting now to do this. I think...
Majority in the editor is true, but separately, it does make me sad that the community site doesn't seem to be used much as a community.
That'll get better when we have project comments, I think.
So what you're saying is that it's no longer a matter of "if" anymore
I think we've always said we intend to implement project comments (but not stars or hearts or thumbs), but that it wasn't the highest priority because we have to get teacher/student accounts finished. Alas, that's still the case, although at least we've made a start now.