On Friday I am heading to Foyles to take part in a panel discussion on Fiction Uncovered FM about literary fiction, under the heading "Is digital making ‘literary fiction’ genre fiction?" With erotic trilogy Fifty Shades smashing sales records has there ever been a better time to talk serious literature?

The discussion appears to have come out of a general concern that literary fiction is being left behind in the e-reading gold-rush. Earlier this month Picador editor Francesca Main tweeted: "Just learnt that for literary fiction in the last year, 88% of sales were paperback vs. 5% ebook. Go print!"

The problem with her assessment is that the physical book market is not growing. As last year's numbers from the Publishers Association Statistics Yearbook showed the bits of the book business that did best (or least worst) last year were those bits where digital filled the gap left by print's decline. The best performing category was fiction, but only because with sales of e-book novels up by £54m (to £70m), they almost compensated for the £57m fall in physical fiction sales.

So, if literary fiction is not picking up sales in digital format, then it isn't performing. And that's not good news for anyone.

One of the difficulties judging the "literary fiction" market is defining which are the literary titles. It is not a separate classification on NielsenBookScan, and neither does it appear as one of the main sub-categories on bookshop websites. Of course, in the physical world this matters less: you can judge these titles from their covers, from the quality of the physical edition, the name of the imprint, who the author is, and where it is in the bookshop. You can even tell from the very the fact that it's not packaged as a 'genre' title.

Online it is less easy to work this out. The reader will need more help, and here the e-book websites are doing a particularly bad job.

I've been checking the 'featured categories' on Amazon off and on for the past couple of weeks, and literary fiction just does not appear as a distinct entity - ever. Even if you drill down to it from within the wider fiction category the title list looks variable. The Great Gatsby is currently the most popular Kindle edition selling, but number two is The Midwife's Confession Diane Chamberlain, which doesn't appear to be a 'literary' book at all: (it's actually a suspense novel published by Mira). I'd like to say this is a one-off but it's not: according to Amazon 'literary' is a hot-potch of classics, romance titles, and the odd past Booker winner. Of recent literary books, only Skios by Michael Frayn and Skagboys by Irvine Welsh feature prominently in this list. Most of the top-selling titles we might consider 'literary' are in fact classified under different genres. Orange winner The Song of Achilles is filed under Historical Fiction (and Fairy Tales!) on Amazon as is Bring up the Bodies.

You might think looking at a Kindle list for literary fiction is like going into a bar for an ice-cream, but even Waterstones.com offers little relief or guidance towards the better books. Literary fiction is not even separated out as a classification on the front page, you have to drill down into fiction and then head to "General and literary fiction", where you find Madeline Miller vying for bestseller space with Maeve Binchy. Foyles does little better, though at least it's featured titles appear more 'literary' than most.

In some ways Kobo is the best experience since "Fiction & Literature" was offered as a top category on its e-bookstore. Sadly the mix of fiction with literature appears to be doing the latter no favours. The topselling book in this category was Her Five Favourite Words, the image for which features two scantily clad models unlikely to be caught on the cover of the next Rushdie. Literary fiction on the iBookstore suffers a similar indignity. Get passed Fifty Shades and Bared to You on its list of "fiction and literature" books, ignore James Patterson and Clive Cussler, and somewhere lurking beneath is Hilary Mantel: not hidden but not promoted either.

Of course I am merely scratching the surface of a larger discoverablity debate that websites such as Anobii, or Goodreads might resolve. And in the print world at least, literary titles can still find their place, in fact perhaps it is easier to find a window through which such titles can be seen because, as smart booksellers know, so much else is being devoured digitally. This is sort of backed up by the numbers. If print fiction is down, literary titles are, at least, not as much down as most. According to NielsenBookScan 2012 has been an ok year for literary novels, with hardbacks such as Bring Up the Bodies, William Boyd’s Waiting for Sunrise, The Sense of an Ending, John Lanchester’s Capital, P D James’ Death Comes to Pemberley all selling more than 10,000 copies in the UK this year. By this point last year just one “literary” hardback had managed that feat – Alan Bennett's Smut.

So to begin answering the question poised by this debate, "Is digital making ‘literary fiction’ genre fiction?" Yes. But if you ask if this is a deliberate decision based around what readers want, or a mechanical mess-up caused by bad classification, you'd have to say it looks like the latter. If one assumes that even digital readers want to read the more serious stuff, then there is an opportunity here to bring up the better books. That literary fiction may be having a softer fall in print than over genres does not absolve the market from making a better fist at selling these titles online.