Microsoft's purchase of Skype seemed like a big move last year, not necessarily the most sensible, but one which could potentially offer business benefits somewhere down the line.
One of the key things picked up be commenters at the time was that this should speed the arrival of Skype for Windows Phone 7. This was 'a good thing' for the platform, when its playing catch-up with Android and iPhone, both of which have Skype amongst other comms over IP solutions.
Except for one thing. Windows Phone doesn't support background running in any form for third party applications.
The net result is that whilst making outgoing calls works fine, there is no ability to use Skype for incoming comms. A fairly major roadblock frankly.
Given that Microsoft own the platform and now the product how much work would it have taken to fix this? Clearly more than the time allowed. Which shows particularly poor judgement on Microsoft's part. They've released a product that is not fit for purpose and which will give those arguing against WP7 as a viable platform some strong ammunition. Here was an opportunity for Microsoft to take whatever delay was required and release the product in a form that would be useful for its users.
By taking the alternative option Microsoft have picked up some (very) short term gain at the cost of significant long term pain. For a nascent mobile operating system that's a gamble loaded with risk.