-군요 and -네요 have almost same meaning and are used as showing wonder and exclamation for new information. But, -네요 has a nuance of a little stronger feeling of wonder and exclamation than -군요. 재미있군요 - I realize that it is interesting! (an exclamation based on evidence) 재미있네요 - I realize that it is interesting! (an exclamation based on evidence and stronger feeling of exclamation than 재미있군요) 재미있었군요 - I realize that it was interesting! (an exclamation based on past evidence) 재미있었네요 - I realize that it was interesting! (an exclamation based on past evidence and stronger feeling of exclamation than 재미있었군요 ) 재미있겠군요 - I suppose that it must be interesting! (an exclamation based on supposition, rather than evidence) 재미있겠네요 - I suppose that it must be interesting! (an exclamation based on supposition, rather than evidence and stronger feeling of exclamation than 재미있겠군요) 그 사람 열심히 공부하는군요 - I realize that, based on evidence, that person studies hard. 그 사람 열심히 공부하네요. - I realize that that person studies hard (stronger feeling of exclamation than 공부하는군요) 그 사람 열심히 공부하겠군요. - I suppose that that person studies hard. 그 사람 열심히 공부하겠네요. - I suppose that that person studies hard.(stronger feeling of exclamation than 공부하겠군요) cf. There is no correspondence of 더군요 재미있더군요 - I realized that it was interesting! (an past exclamation based on evidence) 그 사람 열심히 공부했더군요 - I realized that, based on evidence, that person studied hard.