That depends. Are you happy with the gaming experience/playability of the 290 for your setup? Do you frequently have to reduce eye candy?
The 290 should be able to deliver the goods at 1080p. However, if you are thinking that it's time a change - and you have the spare cash - you might want to consider two GTX 970's (sli), but ONLY if they are warranted for YOUR system (you should take into account future changes e.g. gaming resolution). This is widely considered a 'better choice' (Google 970 sli) than a single GTX 980 --> at >1080p resolutions!!