A couple of weeks ago, ASRock announced that it had found a way to enable CPU overclocking on Intel's H87 and B85 chipsets. Now, ECS has joined the party with a "Non-Z" overclocking feature of its own. The ECS implementation purportedly allows multiplier-based overclocking on H87, B85, and H81 motherboards. You'll still need an unlocked K-series processor to overclock, though.
ECS claims to be the first motherboard maker to enable overclocking on the H81 platform. That said, the H87 and B85 appear to offer more headroom. ECS's press release includes CPU-Z screenshots of a Core i7-4770K cranked up to 4.8GHz on H87 and B85 systems. On an H81 rig, the CPU only hit 4.5GHz. There's no indication that ECS used a different CPU or cooler for that system, which suggests that the lower frequency is a result of either the chipset or the associated motherboard. The latter is the most likely culprit. The H81 is Intel's lowest-end Haswell chipset, and the motherboards based on it probably weren't designed with serious overclocking in mind.
The press release is devoid of additional details, but I suspect Non-Z feature will be enabled via firmware update. It's unclear whether ECS intends to extend overclocking support to all its Haswell motherboards or just a limited number of models. All of the chipset options should be covered, at least.
I'm a little surprised that Asus, Gigabyte, and MSI have steered clear of similar overclocking features. Perhaps they don't want to defy Intel's carefully crafted product segmentation, or maybe they'd rather steer overclockers toward Z87 models with higher profit margins. Either way, overclockers are probably better off sticking with Z87 motherboards. There's no guarantee Intel won't issue a platform firmware update that closes the loophole allowing overclocking on other chipsets.