Wi-Fi is a staple among most smartphone users. While we tend to talk more about cellular data, it's really just there to sustain us as we travel from one access point to another. We aren't just demanding more data at higher speeds, we're connecting more devices than ever before. The inevitable overcrowding of the 2.4 GHz brought about the expansion into the 5 GHz range. Unfortunately, many Nexus devices (and at least a few others) are having trouble making and maintaining connections to this higher frequency band.
Update: According to HTC, this problem is currently only affecting the Tegra 3 (international) version of the One X - not the Rogers/AT&T One X or international One XL. HTC advises those affected to contact customer support, though the channel through which you purchased your device is a good bet as well, especially if it was from a carrier or brick and mortar store where they can exchange the unit immediately.