Lady Gaga’s impromptu guest appearance with Semi Precious Weapons and her stage dive into the crowd during the Friday of Lollapalooza 2010 was one of the highlights of the day one. Check it out above. If Friday was any indication, Lolla fans are in for one heck of a weekend. Within moments of the gates opening, Lolla was off-and-running full speed at Grant Park. Fans caught early sets by slacker-rockers Wavves and The Walkmen, and were treated to a heartwarming surprise appearance by Wilco frontman Jeff Tweedy at Mavis Staples 2pm set. The Big Pink probably scared a few children with the monumental wall of distortion that kicked off their towering showcase, leading into Devo‚ full-costumed geeky New Wave (and yes, they’ve still got it). Chromeo‚ made quite an impression, judging by the many media shout-outs this morning, but it would be hard to top Lady Gaga, who absolutely conquered Lolla with a lavish stage production, costume changes up the wazoo, and the Pop-star professionalism we’ve come to expect from the always-eccentric anti-diva. The Strokes held their own on the other side of the park though, providing a solid, rock-and-roll counterpoint to her Glam spectacle. It was an opening day to remember, and we can’t wait to see what surprises the rest of the weekend holds. Here’s a few more Friday highlights we found buzzing around: - WXRT has full Lolla coverage all weekend long, full videos, interviews, pictures and more. - TimeOut Chicago has a high-minded breakdown of Gaga’s set, approaching her massive appeal from a critical perspective. Hmm. - In addition to a brief rundown of the day’s events, the Chicago Tribune had nice things to say about restroom access and festival walkability this year. We try, guys. - Billboard‘s Friday breakdown features some well-deserved accolades for Raphael Saadiq’s retro soul and our favorite rascals Matt and Kim. - NPR does a quick look back at how far Lady Gaga has come since her festival debut three years ago. - Point. Counterpoint. MTV talks about The Strokes and Gaga’s dueling sets, and why the pairing of the two worked. - The Black Keys played one of the most accomplished sets of the day, according to USA Today‘s recap. - A final bonus: scope out this entertaining list of things overheard and interesting observations from day one of the fest. Nice picture of Mr. Moustache Gaga.