I had no idea that the Emerald developers had been crazy enough to get involved in an illegal Distributed Denial of Service (DDOS) attack on a rival website, hijacking innocent users. Even though it apparently failed to bring the site down, it affected server performance, and DDOS is a serious criminal offence if proved. Technically it seems to have been the web site used for the splash page, not malicious code in the viewer, that was used for the attack, although this needs to be clarified. Even if so, the Emerald viewer was pointed at that web site and I doubt that this will cut much ice with Linden Lab. Trouble is that Emerald is more popular than LL’s own viewer, and has a great deal of power at a time when serious cuts have been made and LL don’t want to risk losing more custom. Perhaps Imprudence, the last remaining full third party viewer listed in Linden Lab’s Third Party Viewer Directory, will at least benefit? (That does not necessarily mean that others, e.g. Cool VL Viewer, are not compliant with the TPV policy, but one should exercise caution in using a viewer not listed in the directory.)
Philip Linden has suggested that users switch to viewers other than Emerald. He hasn’t yet banned Emerald, but LL have been known to take drastic action in the past, even when it hit the SL economy (e.g. the banks), so anything is possible here.
Update
There is no unambiguous evidence that some of the encrypted binaries included with Emerald have been removed that have been known to collect full path names and other information from your computer. This may include your real name if it appears in that path name, as is often the case. The reputations of both Modular Systems and the Emerald Viewer must be considered severely in doubt, and a number of their developers appear to have been directly involved in dubious activities involving the viewer and their sim. In the latter case, IP addresses were collected and matched to avatar names with the intention of revealing alt accounts as belonging to the same individual. Until Emerald get their house in order, I’d advise you not to use any version of Emerald at all.
You may wish to trust LordGregGreg’s Emergence Viewer if you definitely require a feature only offered by Emerald, such as temporary texture uploads for content creators. Sadly, this is not compiled for Linux or Mac – volunteers please! Moreover, Emergence will not be updated, according to his current plans. He appears to have addressed the privacy and malicious code issues, and I would cautiously trust him.
I doubt, however, that you will be banned for using Emerald. But your privacy may not be protected.
Further reading
Starflower Bracken's Blog 