Two things connect the 20 writers on this list. The first is a fascination with the weird and fantastic. The second is their love and affection for the pulp roots of SF. One or two may be just a smidgeon over 40, but will no doubt be among the writers shaping speculative fiction for decades to come. And I have looked beyond Britain where I can to find the most interesting voices in what is increasingly an international SF genre.
Right away this list is set up to be different from the Granta list, which looks at authors younger than 40 who are at least in the process of obtaining UK citizenship. Walter first has to stretch the definition of "young" a bit, presumably in order to fit in China Miéville (who incidentally is mentioned in both the 2003 and 2013 Granta lists, for different reasons). Then he has to use umbrella terms such as "weird" and "fantastic," which he barely even attempts to define for purposes of delineating his list, in order to connect very disparate writers. Granted, the Granta list contains a wealth of styles and approaches (including some, such as Sarah Hall, Steven Hall, and Helen Oyeyemi, which have attracted some attention from SF/F readers/critics), but it does a much better job in its introduction in justifying the connections between the chosen writers and contemporary UK societies. Walter's list, in comparison, looks much more like a host of disparate styles and approaches that underscore a growing lack of generic cohesiveness than anything else. Unless of course the point of his list was to show competing trends toward nostalgic-laden pieces and attempts to make sense of contemporary issues.
Although there are truly some promising names on Walter's list, I have to admit to being quite puzzled over the inclusion of Hugh Howey's Wool on this list. Is it solely due to it being a massive bestseller for a work of originally self-published interconnected short stories? It certainly cannot be because of its brilliant prose or sparkling characterizations, as the stories contain little of worth to them outside of the sort of retreaded SFnal "big ideas" that I suppose are still popular today two generations after the heyday of the "Golden Age of Science Fiction." Likewise, I am left wondering if the mention of Seanan McGuire/Mira Grant is due more to her writing the sort of stories that have the appeal of perishable items: void after a certain date. But unlike Howey, whose omnibus I did read recently and found wanting, I have only read samples of McGuire/Grant's works. However, what I found within them is a blandness that was unappealing. There was nothing within them that promises a writer who'll be an influential voice five years from now, much less 20-30 years down the line.
Although several other of the writers cited I have enjoyed to some extent or another (a few I would consider to be excellent writers), I find it difficult to associate them in a larger setting. Certainly not as a collective of "generational" voices. Part of this is that I'm uncertain if SF/F possesses anything approaching a direct connection to societal concerns that some of the best "literary fiction" pieces do. If Walter's list is to be anything more than just twenty writers whose works he's enjoyed and think will be visible years from now, then there needs to be something stronger binding them. If the 1983, 1993, 2003, and 2013 Granta lists show an evolution of fictions and how contemporary (British) societies and their concerns are presented, then what does Walter's list possess other than a demonstration that there is very little coherence to "SF/F" these days and that perhaps it is ultimately futile to create such a list, as the criteria would have to be so different as to prevent the formation of a tighter, more cohesive literary grouping?