Airplanepics and Edina - for information the seat pitch on the B737-800 comes in at 30", that's a full two inches better than BY
/AMM/MYT with their B757s/A320s - I can tell you that we have very few complaints regarding the legroom on the B737-800, if anything people comment on the fact that they are the most comfortable charter aircraft they have flown on in a long while.
In fact the ony rows which aren't that good are row 14 (fixed upright) in front of the first emergency exit at row 15, and row 32 (the last row) gives limited recline as it is adjacent to the rear toilet bulkheads.
Also one needs to look at how one sits in a seat, if you are going to bring on loads of hand luggage and stuff it under the seat in front (as people can do on most holiday flights), yes you will be more uncomfortable as you cannot slide your feet and legs under to any degree.
The B767-200 is tight, but it is a seating configuration which was inherited with the aircraft from Britannia, and is no different to BYs - 290 seat B767-200s which they have used and are still using in that config since around 1992. And with people wanting the cheapest fare on a whole, the service more than makes up for it. IMHO
As yet I don't think there are any details on the Excel Airways website, but if you do searches on "charter flights to Tobago/Grenada/St.Kitts/Barbados" I know the agents/tour operators selling the seats give full details.
I think the prices are very competetive from what I have heard (not 100% sure) with return trips starting from about £350 in Economy, £550 in Excel Premium and £1000 for Excel One.
I think everyone is looking forward with great anticipation, and like most things so far with XLA, I think it is likely to be well received - the Excel One product is promises to be better than that the UK charter airlines have offered previously on these routes. Certainly the B767-300 will be more comfortable than any of the B767s or A330s used on these routes before.