The fallacies and stereotype peddling in marntamb's posts are legion, but I'm going to make a short list of points to dispel the worst myths / straw men in case anyone wants to move the discussion forward. Please add to the list or tear mine up as you see fit:
1.) White people have always lived in Jackson Heights. In and of themselves, white people pose little risk even if they lived in Brooklyn for a time.
2.) Middle-class and upper-middle-class people have always been an important component of the Jackson Heights community (esp. within the garden co-ops of the historic district). Areas that tend to suffer greatly from gentrification are those with a massive concentration of poverty and/or derelict industrial space that can be quickly converted to high-price housing.
3.) Jackson Heights is one big community that contains several smaller communities cohering around shared language, food, religion, etc. These smaller communities are not discrete categories, but rather have varying degrees of overlap with each other. All of us will have some affinity for one or more of these smaller communities. No single person or group can be said to fully own, control, or speak for any of these smaller communities.
4.) The ethnic makeup of Jackson Heights is constantly changing, but has remained very diverse overall for several decades. Some groups are currently more numerous than others, but that has not stayed and will not stay the same over time. For example, the South Asian area of the neighborhood that I live in has seen a decrease in residents of Indian descent, and a noticeable increase in residents of Nepali, Tibetan, and Bangladeshi descent.
5.) These changes noted above have occurred in the context of major changes (both up and down) in housing prices in Jackson Heights, but diversity remains. The only group in Western Queens that has declined dramatically in recent years are African-Americans. Some of this decline in African-American residents may be explained by gentrification.
6.) People of one ethnic group or race enjoying the cultural products of another ethnic group or race does not necessarily constitute ethnic voyeurism or "Orientalism".
7.) People that are of the same race, ethnicity, class, gender, age, sexual orientation, etc do not all have the same likes and dislikes.
8.) Non-white people may enjoy businesses, foods, cultural programs, etc. that are typically associated with young white people. A yoga studio, chocolate shop, or wine bar will not destroy Jackson Heights. Some people were upset when Starbucks opened in Jackson Heights...the same attitudes were expressed in Sunnyside. I contend that Starbucks has done little to no damage to the neighborhood, and actually attracts a relatively diverse crowd (can someone confirm? I've only been to the one in Sunnyside, which is usually full of diverse teenagers doing their homework.)
9.) Individuals of any and all ethnic groups in Jackson Heights will from time to time display bigoted or discriminatory attitudes. One common attitude expressed from many quarters is the "last one in, shut the door" attitude; i.e. when members of an immigrant group previously discriminated against (say, Italians) then discriminate against newcomers (Latinos and Asians arriving in the late '60's, early '70's). Framing debates about Jackson Heights issues as "insiders" vs. "outsiders" is sophistry.
Flame away!