Found an interesting video on You Tube this evening. In it, a guy compares the size of the Eternal Battlegrounds in Guild Wars 2 with the Cyrodiil map in Elder Scrolls Online. Now, I knew Cyrodiil was bigger than the GW2 maps but I had no idea it was this much bigger. The difference is pretty striking.
Now, a bigger map does not necessarily mean a better experience but it does allow more room to hide and operate outside of the zerg. There are also many more PvE areas in Cyrodiil than what there is in the GW2 WvW maps. Quests, dungeons and town all exist in Cyrodiil and to a much larger extent than in the Eternal Battlegrounds.
All in all, from a sheer size perspective, this is pretty impressive.