I'm assuming the pilot is referring to the WDR (weight data record) transmited via ACARS. The process was changed a couple of months ago to help on-time departures. The pilot can close the door and push before they even get that data just as long as it gets it's pre-push data...except in cases where it is weight critcial and must stay at the gate and get the WDR before push or ACARS is INOP where they must get a copy of the WDR from the gate.
The only time I've heard the pilots call dispatch to get numbers is usually on DCI where there ACARS is INOP since they no longer carry the "wheel".