Dominick,
The two airports are not all that far apart but the problem will be traffic. What time will you be changing planes. You could make it in under 30 minutes easy as long as it's not morning or afternoon rush hours or if there's an accident holding up traffic on either Stemmons Freeway or 183/114. The question I have is why are you making this connection? I guess you have a ticket from CLE or IAH to a DFW flight to either EWR/IAH/CLE. I'm really surprised that it let you ticket that type of connection. As for Continental getting you between airports I'm not sure if they are responsible if that is the way it is ticketed. Now if they rebooked you involuntarily then they would pay for the $35 or so cab fare. But it never hurts to ask or plead for the taxi voucher. There is no schedule shuttle between Love and DFW. I once did get flown into the wrong airport because of a weather reroute and they gave me a voucher without a problem. Of course being elite doesn't hurt. Exactly how did you get this iternary??? Let me know if you have any questions.