Vita *should* get a jump out of the gate from typical early adopters and hardcore Sony fans. For these groups, price is rarely an object. There are at least some consumers who fall outside of both of these circles who are impressed with the Vita's tech and have also expressed interest in buying at launch. Speculating outside the launch is the tough part. How will mass market react to the comparatively high asking price for Vita entry as opposed to the 3DS, which has a growing software library including Nintendo's generally popular IPs?
As for 3DS panic, it's unfounded right now. Yes, upcoming software is a bit light, but I think that Nintendo needs to focus on filling the retail channel with software. If we see retrogression for hardware sales continue through, say, the rest of the quarter, then we can discuss concern. For now, 3DS is coming off of an impressive Q4 and I think it's best to wait and see instead of raise any flags.