I would read that as a choice of either 30 or 15 frames per second. If it was limited to 30 seconds, I would expect it to say 30 @ 15 fps, or some such, and I cannot imagine that it will only do 15 fps. The length should be limited by the size of the card, although I have seen limits like 1 hour, irrespective of card size.

Well... on the other hand... I found this at another review...

...640 x 480, 30 fps, (for 10 sec), 320 x 240, 30 fps, (for 29 min)...

See this Review.

Personally, I'd go with a Canon, but mainly because I prefer SD over XD cards. And I know my Canon cameras do not have such a short limit. I (personally) also avoid cameras with built-in memory... but that's just me...