In keeping with questionable application of AFCI requirements, another dwelling unit AFCI problem you will no doubt be dealing with is wet bar locations in finished basement recreation/game rooms.
Without permanently installed cooking facilities, these areas donít meet the criteria of a kitchen based on the definition in Art.100 stating, "an area with a sink and permanent facilities for food preparation and cooking', so all 15A and 20A 120V branch circuits, including any serving the counter top receptacle outlets, are required to have AFCI protection in addition to GFCI protection for all receptacle outlets within 6-Ft of the edge of the sink. The lighting branch circuit would also be required to have AFCI protection.
Cutting lime wedges and blending margaritas might not count as food prep, but a permanently installed, cabinet mounted microwave oven for melting the cheese on your nachos may be able to qualify as cooking equipment.
I do recall some controversy in the past over whether a microwave oven, permanently installed or not, was considered cooking equipment though, so I guess it could possibly be up for discussion.
If this area were classified as a kitchen, then no worries, but otherwise, the issue I have with this requirement is that AFCI's will nuisance trip frequently when certain motor operated cord and plug connected small appliances are plugged in to these counter top receptacle outlets.
Another issue is if I also have a sump pump for this wet bar sink installed below, if it's not considered a kitchen, then AFCI protection would be required for the branch circuit serving this 120V receptacle in addition to GFCI protection if located within 6-Ft of the sink, measured in any direction. An AFCI nuisance trip with a sump full of gray water is a bad situation.
The '08 NEC... it's the gift that keeps on giving!