Calm the fuck down.
Look, until the official announcement tomorrow, you're not going to know anything, so don't fall for conjecture and guesses. Here's a really simple thing to keep in mind: anyone buying LJ isn't buying the code, that's open-source; they're buying the users. Now, if they did this and then deleted accounts, they'd lose those free users, who would be pissed and go to other blog sites. Now, let's crunch some numbers:
* Total accounts: 5642122
* ... active in some way: 2443918
* ... that have ever updated: 4163039
* ... updating in last 30 days: 1426429
* ... updating in last 7 days: 905016
* ... updating in past 24 hours: 330712
* Free Account: 5544357 (98.3%)
* Early Adopter: 14228 (0.3%)
* Paid Account: 93307 (1.7%)
* Permanent Account: 1622 (0.0%)
...do you honestly think they want to buy all this, and then LOSE 98% of the users they just bought? Hell, even if they came in and said "no more free accounts", they'd lose that. Not saying longer term projects may not be in that vein, but it isn't as if you are going to wake up tomorrow with no account, or discover you have 48 hours to pay up or fuck off. So, relax, chill out, and stop trying to back up your whole LJ as fast as you can.
It does make me mention, though: paid accounts aren't expensive, dammit. Less than 2% of LJ is supporting it...that's kinda sad. Pony up, kids. I can't say that I blame Brad one bit for selling it all...he's got a right to make some money for his creation, doesn't he? He sure isn't getting it from his users.
Scary isn't it? Only 43.3% of the accounts on LJ are considered "active in some way", and only 25% of LJ accounts have updated in the last month. I'm willing to bet that any paid accounts actually have updated in the last month, but that's still only 6.5% of truly active users paying for the whole site. Go without one overpriced coffee drink a month, and there's your paid LJ. Don't supersize your fast food once a week, there's a paid LJ. Get your news online instead of buying a newspaper, there's your paid LJ AND saving paper. Think about it.