Well, we don't know how soon it's going to be introduced, but the next Curve is most likely the BlackBerry Curve 9360, unveiled yesterday by UK-based website OneMobileRing. Previously seen in a leaked Bell roadmap, the 9360 should feature a 2.4 inch HVGA non-touch display, BlackBerry OS 7, HSPA, Wi-Fi, 3.5mm headset jack, and an 800MHz processor.
You can see the Curve 9360 below, compared to the old Curve 9300 in the first two photos, and the Bold Touch 9900 in the third one.
source: Unwired View