A couple of reasons spring to mind.
There's a smaller number of lenders out there and some of them either aren't lending much at all or their rates are not competitive. So the ones that are actually lending or have competitive rates (AIB, Bank of Ireland, ICS) are getting a much bigger slice of the pie, even though the pie is much smaller. 3,259 new mortgages to the value of €577 million were issued during the first quarter of 2011 - IBF figures. That's down a lot on the boom years but it's stll a lot of processing.
Many lenders have redeployed staff from their new business area to deal with their only growth area - arrears handling. So chances are there's a lot less people working in the new business areas of the various lenders.
I hear two weeks is average turnaround time for a new application these days.