The good news are that SP2 is available for Office 2007 products. Please refer to the following links with all information you may need.
SharePoint Product Group team blog
Announcing Service Pack 2 for Office SharePoint Server 2007 and Windows SharePoint Services 3.0
Office Sustain Engineering or CAPES blog
My colleague Stefan Goßner blog
The first update after SP2 will be called April CU. We highly recommend that SP2 should be installed first and that means please start with SP2 and the April CU should be available in days. More information I will post here ASAP.