More details are starting to eek out of MIX10 in Las Vegas, Microsoft's annual symposium on all things Redmond, the latest being more hardware details about Windows Phone 7 Series handsets due out at the end of the year.

According to Charlie Kindel, who is in charge of Microsoft's Windows Phone developer strategy, the company will do away with support for memory cards and instead force hardware manufacturers to use only internal memory - and lots of it.

"Windows Phone 7s won't support user-replaceable memory cards... no MicroSD cards for your music..Some phones could have a MicroSD locked under the battery, but it won't be user-replaceable", reports PC Magazine's phone editor, having sat in a briefing with Kindel.

Also gone will be apps that run in the background which, "create an end user experience where battery life and responsiveness of the system becomes … inconsistent", Kindel said. "We focused on getting a set of experiences right where we didn't have to support [multitasking], but we will over time".

The news is likely to come as a surprise to some that would expect the new operating system from Microsoft to be multitasking.

The company used the MIX10 event to detail a number of new elements and capabilities of the new phone OS, including information about some of the apps the company is planning on launching when the phones start to be released at the end of the year.

Other details included hardware features like screen resolution and processor requirements.