It's a question to which the answer for just about any phpBB user is :YES
There will certainly be users who will use it : I know I will, but that doesn't imply that people are doing to stick with it (if you consider it a "style").
I'm not following the development but it's like asking a Win311 user whether he will use Win95. Either the user will stick with MS, in which case sooner or later he will have to use it, or he'll move to another OS depending on the experience.
Spelling is freeware, which means you can use it for free.
On the other hand, it is not open source, which means you cannot change it or publish it in a modified form.