While some improvement is needed in this area, I think the problem is at the individual property level rather than Marriott corporate, although corporate is responsible for making and enforcing policy.
My own personal experience has been that all stays have posted in a timely manner over the past year including Vail, LAX Ren, numerous properties in PHX, LAS JW, Garmisch Ren, Heidelberg, JW Ihilani, DFW South, JAX CY, Breakenridge VC, MKE and Curacao. Generally posting can take up to 2 weeks for US properties, although most post within 5 days. Friday's check-outs from the PHX Marriott and PHX Residence Inn both posted today. International properties can take up to a month. I think the reason for this is that at some international properties they batch transmit their info once a month in an attempt to save time/money (just a guess). After waiting 2 weeks for US and 1 month for International, I would call MR customer service if your points have not posted.
In previous years my experiences with posting problems have been isolated to international properties and it required a call to MR customer service. With the new e-folio, I would check with the CSR and see if you can email them that info directly as opposed to a fax, if the international cost is too high.