Here's a chatlog from the #namecoin channel... couldn't find anything about this on the forums already, sorry if I missed something:
[2013-08-15 10:19:28] <Jeremy_Rand> okay, so the last 6 blocks have had no transactions in them... anyone know why that might be happening?
[2013-08-15 10:20:11] <c0rw1n> no idea, maybe try to message DrHaribo, he should be on freenode and operates Bitminter
[2013-08-15 10:20:29] <shader> are there no transactions waiting?
[2013-08-15 10:21:11] <Jeremy_Rand> it actually seems to be fairly common... looking at the explorer, it's common for there to be 6 or so blocks with nothing, and then like 20-30 transactions in the next block
[2013-08-15 10:21:27] <Jeremy_Rand> I'm pretty sure that's statistically not by random chance
[2013-08-15 10:21:29] <shader> so, some miners aren't doing anything?
[2013-08-15 10:21:47] <Jeremy_Rand> that's what it looks like to me
[2013-08-15 10:21:51] <Jeremy_Rand> but I'm not an expert
[2013-08-15 10:22:38] <c0rw1n> well i know i'm mining namecoin, but i have no idea what my pool operator's doing
[2013-08-15 10:22:51] <Jeremy_Rand> ok, my transaction just got into a block about 10 seconds ago
[2013-08-15 10:22:57] <Jeremy_Rand> even though it was sent an hour ago
[2013-08-15 10:23:11] <Jeremy_Rand> and there were 158 tx's in this new block
[2013-08-15 10:23:17] <Jeremy_Rand> so a lot of people were waiting
[2013-08-15 10:23:32] <shader> hmm
[2013-08-15 10:23:36] <shader> that doesn't sound good
[2013-08-15 10:23:47] <Jeremy_Rand> agreed
[2013-08-15 10:24:00] <shader> do you think it's possible to track down which miners were responsible for the last few blocks?
[2013-08-15 10:24:14] <Jeremy_Rand> no idea
[2013-08-15 10:25:11] <Jeremy_Rand> I can see their 50NMC tx's to themselves... so we could probably track down the miners via blockchain analysis that way
[2013-08-15 10:25:15] <Jeremy_Rand> but that sounds like a lot of work
[2013-08-15 10:26:46] <shader> that one miner seems to get a ton of the blocks, and doesn't do any transactions...
[2013-08-15 10:26:55] <shader> N4BbUHfarRXx8GBNj9DHAqthhuvxsKpnZE
[2013-08-15 10:27:04] <c0rw1n> wohoha okay, i wanted to see if my pool had minted that 158 tx block, and nope : we're at 100M PoW and 99.25% CDF, mining for 7 hours
[2013-08-15 10:27:24] <shader> lol
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[2013-08-15 10:53:16] <Jeremy_Rand> of the last 15 blocks, only 3 have any transactions
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[2013-08-15 10:55:50] <Jeremy_Rand> and all 12 of the empty blocks are by the same miner
[2013-08-15 10:56:01] <Jeremy_Rand> I believe that would make this a 51% attack?
[2013-08-15 10:58:43] <Jeremy_Rand> is there any way to track down the miner's identity from his payment address? I'm wondering if it's a pool or a freelancer
[2013-08-15 10:59:14] <Jeremy_Rand> whoever it is probably has the ability to reverse transactions / steal names if I understand the implications of a 51% attack
[2013-08-15 11:05:51] <c0rw1n> ah but
[2013-08-15 11:06:00] <c0rw1n> only the current transactions
[2013-08-15 11:06:17] <c0rw1n> if he wants to screw old transactions, he has to rehash each of the blocks
[2013-08-15 11:06:30] <c0rw1n> AND keep up
[2013-08-15 11:06:44] <Jeremy_Rand> he has 80% of the hashpower, that sounds quite doable for names that were registered recently
[2013-08-15 11:06:57] <c0rw1n> he has waitwut ?
[2013-08-15 11:07:18] <Jeremy_Rand> 12 of the last 15 blocks have their mining payout to the same Namecoin address, i.e. the same miner
[2013-08-15 11:08:53] <Jeremy_Rand> I think this is a Bad Thing (TM)
[2013-08-15 11:09:28] <c0rw1n> i hope it's a bug in a pool and will get fixed soon
[2013-08-15 11:09:29] <c0rw1n> oh yes it is
[2013-08-15 11:10:01] <c0rw1n> namecoin is a solution to so many problems
[2013-08-15 11:10:46] <Jeremy_Rand> I wonder how long this attack has been going on... anyone want to look through the block explorer and see how long he's had this much of the hashpower?
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[2013-08-15 11:15:32] <mhanne> received 6609 payouts since 12/06/13 02:26:56 (didn't check if all are generations but the vast majority seems to be 50nmc exactly)
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[2013-08-15 11:19:19] <shader> makes you wonder what they'd want to do it for... I mean, it's not really a very logical attack
[2013-08-15 11:19:45] <shader> most likely they set up merged mining incorrectly or something
[2013-08-15 11:19:48] <Jeremy_Rand> crap, so over the past 9 weeks he's averaged 71% of the hashpower
[2013-08-15 11:19:59] <shader> ...
[2013-08-15 11:20:30] <shader> and the difficulty isn't low either, so they must be one of the mining pools
[2013-08-15 11:21:06] <Jeremy_Rand> if it's a pool, then one of the pool's users should be able to trace his 50NMC generation to their payout, right?
[2013-08-15 11:22:00] <shader> true
[2013-08-15 11:22:17] <shader> are there any tools for tracing transactions?
