Skype Journal points to some interesting data suggesting a slowdown in growth rates for Skype, based on the rate of increase in concurrent user numbers. I also track a few stats (daily downloads and daily minutes of use), and I can see a similar trend. Throughout March, average daily downloads were running between 450 - 500k, though in April this fell to the 380 - 430k range, and so far in May we are consistently below 400k (most recent observation over the weekend was just 320k). Admittedly, it's always slower on the weekend, but my stats suggest a 9% decrease over the level of the previous weekend.
The Skype Journal post rightly points out that there have been relatively fewer releases of late, so perhaps that is a contributing factor, but what about the usage side of things? In both March and April, the average of my observations of daily MoU were 41.7m per day. So far in May, we are at 39.9m, despite more concurrent users online and a larger overall user base. Is average Skype usage growing less intensive? Possibly. The weather is improving, even in England. Other possible explanations which spring to mind are:
- Skype's differentiation as an IM client is gaining traction, and this is diluting voice usage. Overall stickiness may be increasing, but this doesn't show up in the MoU stats, which are one dimensional.
- SkypeOut/SkypeIn usage scenarios are increasing their share of overall usage, which again is something invisible in the MoU stats.
Perhaps it's time for Skype to start breaking out other KPIs so we can better understand how usage is evolving. Publishing SkypeOut minutes, SkypeIn minutes, and IM sessions would give a much clearer and well-rounded picture, wherein on-net MoU alone may be less meaningful over time.