There is a lot of fishy stuff about this launch. It came out 75 minutes later than expected and its possible that others were mining on the new block chain before it was posted to the forum. It also came with missing DLLs files for the Windows install
Welcome to the fun world of software releasing! It's why I don't release much software. This one would be even worse than average - in order to launch with a genesis block of verifiable timing they would have had to modify and compile the viewer immediately before launching, and the Bitcoin build process is really gnarly and non-automated.
and it didn't run in server mode by default meaning that many solo miners may have lost a lot of blocks. Of course there was a lot of rush to mine this new block chain but many people not realising they required to server switch and still seeing zero balance took to the mining pools despite the very low difficulty. The mining pools really made the situation much worse as all the hashing power was now centralized mainly at BTCguild.
Bitcoin has never run in server mode by default - I think the official client may even require -server if you run the GUIless bitcoind program. Anyone that didn't know this probably shouldn't have been mining solo anyway. At the block rates IXcoin and I0coin reached when they first launched, you apparently pretty much had to have long-polling support in order to get any non-stale blocks, which meant setting up pushpoold and blkmond. That's a lot harder than remembering to pass the -server flag and has lots of potential for breakage.