Something I've noticed in pro games over the month or two, particularly Korean, is this variation on a classic joseki, 7 being one line further than the normal solid one space jump at a. I also saw Park Junghwan 9p doing it on the 4th line at b. I've not read/heard any commentary on this new trend, but I imagine it's trying to be a bit more efficient, and as white played the hanging connection of 6 the attachment at c isn't working so well yet as black can hane on the outside and gets a useful atari. I don't think I've seen this further, thinner moves with the solid connection for 6. I don't think I'd be alone if reviewing this move in a weaker player's game I said "Hmm, that's a bit strange, you leave some bad aji there, probably better to be solid one point jump (or the other joseki moves there like peep if the situation warrants it)". One game Lee Sedol as white did use the thinness to good effect later (I'll try to find it), it will be interesting to see how it develops. There are some older instances of it (e.g. 1995, 2008 from quick check on ps.waltheri.net) but it seems to be popular lately, I wonder why.
Park Jungwhan doing it on the 4th line. It seems rather painful/inefficient when he answered with the iron pillar, but he then used that to jump further into the centre.
so the evaluation of this line in the context of more active black openings might be changing.