What's the reason behind the sudden influx of the English word "word" in Chinese slang?
word 天 is chinese slang for 我的天. 

With an increasing English skill level of Chinese speakers, Chinglish or rather the Chinese counter part of Chinglish is becoming more and more common. 


Names are often translated using English sounds with Chinese chracters. Ex: Stanford University = 斯坦福大學
Some store names are starting to use English sounds with Chinese characters
Bread Ice / 不賴的冰 http://sunyat.pixnet.net/blog/post/63815917-%E9%AB%98%E9%9B%84-bread-ice%E4%B8%8D%E8%B3%B4%E7%9A%84%E5%86%B0-%7C-%E5%8F%A4%E6%97%A9%E5%86%B0%2B%E5%B8%95%E5%B0%BC%E5%B0%BC%EF%BC%8C%E7%9C%9F%E7%9A%84
But these words are not limited to only English. Some even use the local dialect (Taiwanese) and convert it to Standard Chinese. 阿兜仔 is taiwanese slang for forienger (specifically white foriengers) https://www.youtube.com/watch?v=u5WUtW0Dvik


I think overall it's just people becoming more and more creative with how they use slang.