-고요/구요 is very commonly used in daily conversation. 오늘은 어제보다 더 춥고요(or 춥구요), 내일은 비온대요. It's colder than yesterday, and they say it will rain tomorrow. 이건 비빔밥이구요(or 비빔밥이고요), 이건 고추장이에요. This is bibimbap, and this is red pepper paste. -구요 is originally the 경기도 dialect, but many Seoulers say it also. Southerners hardly say -구요 since it grates on their ears.

Ok, Haily did show examples enough, I think. But -구요 is not really standard or right form to say. Standard form for the dictionary is -고요, but in modern spoken Korean language, so many people tend to use it, so we do understand it clearly but for the record it is wrong form to use. But what can I say? Language is alive thing. It can change the rule anyway. But for now, -구요 is wrong form from -고요.