The co-branded Panasonic-Leica 45mm f2.8 OIS macro Micro Four Thirds lens has been reviewed in a detailed review at Lens Tip. Conclusions and samples taken with the Olympus E-PL1 can be found on the last page of the review.
The Leica 14-50mm f2.8-3.5 Four Thirds lens got a review translation in english at Lens Tip. The original review was posted in 2007, when Four Thirds was still the primary focus of Olympus and Panasonic.
The Leica 90 f2.8 Elmarit-R, an R-series SLR lens, is reviewed as a lens to be used on Nikon-mount (D)SLRs at Nikonblog.net. This is an experiential review with web-size samples included. As usual, we won't reveal the findings here, so be sure to check it out if curious on how it performed.
Episode #2 of the old-on-new series at Photozone is a review of the Leica 50mm f2.5 Summarit-M lens mounted and tested on a Sony NEX-5 mirrorless camera using the appropriate lens mount adapter. This is a standard format P-Zone review, with conclusions and samples as usual on the last page.
It is like time at PDN Gear Guide where they have published their short one-page experiential review of the Leica Summilux-M 35mm f1.4 asph lens. This is an M-series lens, to be used on digital and film M-series rangefinder cameras - and adapter-mounted on many other cameras, including the increasing in popularity mirrorless compacts.