I visited before it hit the English language media, so I think maybe the experience may be a little bit different now and there are likely a lot more people!
If you plan on going, make sure you stop by the cafe right away when you arrive! When I went, I arrived around 11AM, thinking I could get in for lunch after waiting an hour or so. Boy, was I wrong! I had to take a number and arrive at around 5:30PM or 6PM to try and get in.
The line may appear short, but that is because they time tickets to allow you to wait! Also, note that the waiting area is outdoors. In the winter, they do provide you some hot tea and lap blankets to use while you wait, so that's nice, but I can only imagine how hot it would be in the summer.
While you wait, you are given a menu (no English). Since I don't know Japanese, I ordered by picture. So, you can definitely resort to that, too. You order before you even sit down, so the service is great!
Here, I would definitely recommend getting a set/course menu. The value is pretty good and because, with it, you get a latte that you can customize with your favorite Moomin character.
I chose to get the Au Gratin Set with a smoked salmon side salad and rice. For my latte, I chose to get Moomin!
This is where it gets its claim to fame. Unbeknownst to me, as a single diner, the staff brings you a HUGE plush Moomin to keep you company as you eat. The Western news services are calling it "anti-loneliness" cafe, etc. I legitimately just wanted to go for the Moomin theme (I am used to traveling/eating alone), but I got a BONUS!
So, this is one place where it pays to be a lone diner.
I watched as a group of two Japanese girls pleaded to get a Moomin at their table after they saw the staff bring me my dining companion. They failed. haha
Plus, the as another bonus, the middle-aged Japanese ladies next to me felt sorry for me and they gave me their collectable coasters. YAY!
I felt very successful after that dining experience.
Tokyo Skytree Station (Tobu Isesaki Line)
Oshiage Station (Hanzomon and Asakusa Line)
Station side of Skytree Solamachi on 1F, by the parking lots.
It is across the way from a Tokyo Banana store.