When creating updatable local views, the default setting for the SQL Where clause is slow. Look at the Update Criteria tab of the View Designer. On the right is a label "SQL WHERE Clause Includes". The default choice is "Key and modified fields". This will create an update clause like this:
UPDATE MyTable WHERE Key = KeyOldVal, Field1 = Field1OldVal, Field2 = Field2OldVal SET Field1 = Field1NewVal, Field2 = Field2NewVal.
You can see that this could cause your update to be very slow. One solution is to index each field so that the UPDATE is optimized. However, this is not the best solution. Make sure you have a Primary Key in every record and select the first option in "SQL WHERE clause includes". This causes only the key field to be included and will dramatically speed up the UPDATE.
Craig Berntson
MCSD, Microsoft .Net MVP, Grape City Community Influencer