No? It seems to be working up well enough so far for e.g. ODT, or indeed the web. A file format that might need to be read in 20 years seems like one of the few cases where the super-verbose XML style is actually appropriate.
I'm all for super-verbosity in useful information and flexible structure, but XML is also super-verbose in terms of redundant markup. Compression helps a bit, but it still costs processing power for no real reason. See the good ol' S-expressions vs. XML discussion, recently reincarnated as JSON vs. XML.
