Vista SP1 RTM

So Vista SP1 officially went RTM today with one major headache - it won't be available for download until mid-March. Microsoft hasn't said yet what the reasoning here is, but either way I guess that clean install + SP1 I've waiting to do will have to wait another month. I don't understand the holdup since they already made it a year past the official release date of Vista (by a few days) without releasing a service pack. Wasn't that the point? :)