Earl's Court, as mentioned earlier, was a big place for Aussie backpackers (and if you draw a line on the District Line down towards Wimbledon, you'll find even more around Parson's Green as they're priced out of their former stomping grounds). Young, on a budget, looking for a bargain to stretch out their finances.
The only bad experience I had with a hotel in Earl's Court was when staying there in early October and the weather was unseasonably cold. Earlier in the day, reception at the 3-star hotel told us there was maintenance work on the heating system but they had spare blankets. When we got in that night and asked if we could have extra blankets, the answer was, "no. We don't have any left." So we put coats on the bed and 'made do' with what we had.
If you're going during a very cold snap, it all depends how warm your coats are!
Now: Kensington & Chelsea is the exclusive well-heeled area of the city. The term "Sloane Rangers" was coined for yuppies (Young Urban Professionals) that lived around Sloane Square in the area in the 1980s. The song "West End Girls" by the Pet Shop Boys tells the story of upper-class West End girls mingling with the rough-and-ready East End boys, and Kensington & Chelsea is the west end (to Mile End and Stepney Green's east end). Princess Diana is synonymous with the area.
You get the idea!