Of course, it's not like the writing wasn't on the wall. With the introduction of the Visor Edge, it became clear that the Springboard form factor was holding Handspring back from making smaller devices. On a more general note, Handspring had previously announced that they were getting out of the PDA business altogether, moving instead to cellphone/PDA combo devices like the Treo.
However, according to the article, the lack of a Springboard slot doesn't mean that the Treo line won't be expandable. Currently, one Treo model comes with a Secure Digital expansion slot. If Secure Digital technology advances as exptected, the expansion format could provide many features currently covered by Springboard modules, from backup to Bluetooth.