Late 1987 shift

I think this gets underlooked. There definitely was a shift in late 1987 towards the more official late 80s but it didn't stick out as much as mid to late 1988 or 1989 going into 1990, plus there were some heavy mid 80s holdovers compared to late 1988 to mid 1989, which had a lot but not as much.

Here are there the things that have a late 1987 a bit more of an offical late 1980s feel and marked a shift.

- Nes becomes super mainstream with landmark titles such as metroid, punch out and zelda released in late 1987. Nintendo merchandise, ads, magazines start exploding 85-mid 87, barely had anything like this. 
- 90s style black box TVs become more  visible in stores and houses as opposed to most being mostly being wide and/or silver or grey
- Amiga 500 is more recognized as 16 bit gaming machine with enough of a games library by late 87 compared to earlier. 
- TMNT is aired on TV, with puzzles and earliest merch hitting the stores in winter 87
- Despite fashion being largely stereotypical 80s, early 90s things that would pop out more in 88-90 start to appear more often compared to 86-87: curtained hair, hair flip closer to 1989-1991, straightened or natural hair in females, soul patches and facial hair, circular rimmed glasses, hi top fades as a more wide spread trend, pony tails/long straight hair on men, earthy colors, zig zag pattern design. 
- Many hit pop song start showing more serious late 80s/ 90s style sound elements compared to 1986-1987, even if there are still a ton of very mid 80s sounds in songs that sound straight out of 1984-1986. 
- Micheal Jackson's Bad defines Micheal Jackson's  late 80s image, which is popular until 1990-1991, with a movie tie inn just a year later in 1988, possibly even filmed in late 87/early 1988 
- Simpsons shorts (tracey ulman show is not obscure it is popular), married with children, ducktales, full house, degrassi high all debut
- Late 80s Hip Hop is more solidified and detached from the mid 80s with acts like Eric B and Rakim, KRS One, and Public Enemy leading the way
- Alternative rock becomes a more established mainstream genre with hits by Husker Du, REM, the Replacements and They Might Be Giants among other and more than just indie pop or one off hits like in 1986. Alternative rock genre shows influence in big hits by pop-rock groups such as INXS, U2, Suzanne Vega. 
- New Jack Swing starts becoming a thing. 
- Grunge is more established as a proper underground genre with more notable releases by soundgarden, green river, screaming trees and white zombie (before they were metal)
- House starts sounding closer to acid house and techno with big hits by Bomb the Bass "Beat Dis" and Marrs "Pump up the volume"