I'm not really where to post this topic. Since I set my meteobridge up to report to the internet, the pressure readings that the aculink bridge is reporting on My Backyard Weather and what Wunderground reports differ by 1.44. The bridge is reporting bridge pressure and WG is reporting absolute I guess. Is that normal? WG is reporting 28.42 and MBYW is reporting 29.86.
The Acurite bridge hardware puts out absolute (aka station) pressure data.
Depending on your widget settings, MBW will display the absolute pressure, the absolute pressure with a fixed adjustment, or the proprietary "Acurite" method. If you haven't changed any settings, MBW is probably displaying the "Acurite" method.
What your meteobridge is reporting to wunderground will depend on its particular settings. I suspect it might be reporting an altimeter reading based on your elevation, but you'll have to verify that.
In my experience, wunderground doesn't seem to care what method of pressure reporting you use. It just takes whatever you report.