For the more powerful devices, Acer will be designing those in house. Those should be based on the Qualcomm Snapdragon processor. Compal Communications will be the one to actually produce them.
For entry level devices, Acer should be moving on fairly quickly. Devices at that level don't have to run the latest and greatest version of a given platform. For higher end devices, Acer can go ahead and move on Android based phones too. Google seems to almost continually release new versions of Android and so far, upgrading to at least one new version hasn't presented much of a problem to users.
For Windows Mobile though the big expectations are with WinMo 7, due later in 2010. It would be nice if Acer designed the phones using the new WinMo 7 chassis specifications even if they put WinMo 6.5 on them now. It is difficult for the average consumer to justify the high-end smartphone premium when it isn't upgradable, especially when the iPhone and Android devices are easy to update.
There are no hardware specs, other than the processor, for the Acer phones. I am sure rumors and even spy photos will be available in the coming months.