Humboldt Park is a Chicago neighborhood that is west of Wicker Park, south of Logan Square, north of Garfield Park, and east of Austin. It is an area where many former residents of the projects moved when given housing vouchers, but it is also starting to recieve some hipster spillover from Wicker Park.
Most of the hipsters (and other white people) live east of the actual park called Humboldt Park, one of the biggest in the Chicago park district. The park contains a swimming pool, a lagoon, numerous walking trails, playgrounds, food stands, bike paths, and more. This was not always the case, but right now it's clean and family-oriented, and safe during the day. (I never went there at night, so can't vouch for its safety then.)
West of the park, one finds an interesting situation: the blocks are alternately litter-filled and vacant lot-filled, with loud music, drug dealers, and obnoxious teenagers; and quiet, tree-lined, almost suburban-feeling streets with signs displayed prominently. The signs give the name of the block club and state rules such as "No Drugs," "No Litter," and "No Loud Music". The lawns are well-kept and planted with flowers. The block I lived on this summer did not have a block club, and my landlord explained that the residents had gotten together and just decided they'd rather be free to do whatever they wanted.
So far, there are few (if any) hipster establishments in Humboldt Park, particularly since most hipsters fear living west of the park itself. (My roommates and I, and one guy across the street, were the only white people on our block or the next few over.) Most of the businesses are car dealerships, small Latino grocery stores, laundromats, and bakeries. But rent is cheap, and I expect that Humboldt Park will go the way of Wicker Park, though it might take a little more time.
Humboldt Park has a large and active Puerto Rican immigrant community. In the park itself, many booths sell Puerto Rican flags and t-shirts and food. East of the park is a stretch of Division Street known as Little Puerto Rico, marked by metal sculptures of the flag. Puerto Rican restaurants, music stores, supermercados, and other establishments are common. There's even a dance school and political organizations opposed to further gentrification. At night, Little Puerto Rico's many bars open, and old men sit outside the bars or their apartments and chat until late into the night, or drink and play checkers at one of the outdoor tables.
It is inconveniently not located directly on any of Chicago's train lines, though both the green line and the blue line are easily accessible by bus. This is probably why the neighborhood is resisting gentrification and the surrounding ones are not.