Hi Penny!!
What I mean by the Hottest ticket is that these ressies are the hardest to come by. ALL this applies only if you WANT to do Brunch at Palo. Of course, if you don't care for it, then this wouldn't at all be important to your Cruise experience .. (but I do like the Palo experience at Brunch myself)..
Personally, I think Palo Brunch is 'hotter' than dinner because:
1. Dinner is served every night at Palo. Brunch only on AT SEA days (3 in our case - including the Key West day I think.. unless itinerary changes..).
2. Brunch is spectacular (from experience) and you can probably search for pics and trip reports of these 'all-you-can-eat' at Palo experiences. Very cool.
3. My research (DIS and the Passporter Board threads) tells me that by the time 75 days come around, people have problems booking the Brunch online..even 90 days bookings can be tough if many people are seeking Brunch for that cruise... so BOOK IT FIRST if you get to do it online and there's one available

is all I meant

.
What I've also learnt is that
DCL sets aside a number of ressies online and then you can also book some on the ship when you board. So, if you miss the online ressie you can still try your chances at getting one when you board the ship... (anyone with experience on this do let us know..). Remember also that people change things around depending on their interests so online availability could change - so keep checking if you're looking

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You can also have TEA at Palo but from reading about HIgh TEA at Palo, it doesn't seem to be as spectacular as Brunch -- and the prices are different too ($5 for High Tea and $15 for Brunch and Dinner is $15 too).
This is from my personal experience.. anyone else has differing opinions to offer?