According to Nate Ulrich of the Akron Beacon Journal, the Cleveland Browns have officially joined a long list of teams with ticket sales woes that will not be exploiting the NFL's newly relaxed blackout rule. Only the Tampa Bay Buccaneers have announced that they will take advantage of the rule, dropping their sales requirement down to 85% to avoid blackouts.
The reason for the lack of interest on the teams' end in dropping the blackout requirement to 85% is likely due to the revenue split between the home team and the visiting team for every ticket the home team sells beyond their blackout requirement. By not lowering the percentage, the home team gets to keep all of the additional revenue they generate from sales beyond 85%.
For the Browns' part, the move was probably the right path to take. They have had trouble selling tickets in recent years, but they have a notoriously enthusiastic fanbase with a core group of fans that would never abandon their team. They may have to black out a couple of games in Cleveland in 2012 if ticket sales don't go well, but in my opinion, that's a better result than giving your product away for free over the airwaves.
The real news since the NFL announced the relaxed blackout rule is that only one team has taken advantage of the rule, which was clearly intended to ensure that teams were able to air their home games in their home markets live. As I mentioned above, the hangup is likely due to the revenue split for tickets sold beyond the 85% mark (or whatever arbitrary percentage the team in question decided to use). The NFL may revisit this issue next offseason, but for now, it hasn't effected anyone beyond Tampa Bay.