Granted, the main incentive for me seeing it were the following three things:
1. Stephen Fry's directing
2. The presence of Mr Peter O'Toole and Messrs Jim Broadbent and Simon Callow
3. And most importantly: Richard E. Grant playing a Catholic priest.
The above three were certainly not disappointing in the least! Jim Broadbent was brilliant as a drunken army major. REG, Callow and O'Toole's roles were pretty much cameos and they probably only had about seven or eight minutes collective screentime (but memorable screentime at that, particularly O'Toole's old colonel and Callow's disposed European monarch), but there was plenty more to enjoy, such as the enchanting younger cast. The lead is absolutely gorgeous and so sincere in character. He looks a bit like a young version of Hugh Laurie. The lead's apparent nemesis (the rival for the affections of the heroine) was a dead ringer for the Duke.
In fact, the film as a whole had a little resemblance to Moulin Rouge, with the tragicomedy elements and much whirling party scenes with dancing and bright colours and the like. However, it took itself a little more seriously and was more of a social commentary on the shallowness of 1930s high society.
So, all in all, I liked it. Probably the Noel Coward in me speaking....I'm a sucker for dry wit and inane jokes. :)