I'm about 200 pages into Infinite Jest.
Course, while reading it I've also read Crime and Punishment, Speaker for the Dead, and Xenocide.
Infinite Jest is good, sofar, but I really should keep a legal pad for all the names and abbreviations. It's a huge book told from who knows how many different perspectives (and the writing style changes drastically from one perspective to the next). The endnotes take up another 50-100 pages easily. But there seems to be quality in it, so I'm not being daunted. Just struggling with time (C&P was started when I left IJ at work, and my wife went into labor, the other two were done during the two weeks at home)