While a lot of the hype around Google Wave might have passed by now, the concept still allures and frustrated people in equal amounts.
Over time Google has been improving Google Wave, and while it is still a preview quality product, for those that stuck with it the experience has become much better over time.
In a recent survey Google found the following three issues with Google Wave which needed to be countered:
Integration of Google Wave with existing technologies, Google's or otherwise was also poor. People had no simple means of getting notifications when they received a new wave. While you could always use a Chrome extension, or a Firefox add-on or even a native application to receive wave notifications, most people just hoped for a Wave which would integrate with their email, where they could check their email in wave, or check their waves via email. In the least an email notification system, and such has now been implemented.
One can now set notification options for their Google Wave inbox, and get an email notification when they recieve new waves, or old waves are updated. The system is intelligent enough to not send multiple notifications for quickly changing waves, or for open waves.
Most people already have some or the other notification system for when they get new emails, and with this, they now have an indirect look into their Wave inbox as well. As Wave becomes more stable and reaches maturity, we can hope for better integration with other tools and technologies. The fact is though, that Wave was designed as a web application, and having a Wave client doesn't make as much sense as one might think. Using Wave requires one to abandon their old concept of email-like conversations, and approach the new concept of waves head on. More than anything else, this is perhaps the biggest challenge that Wave will face.